From 814ec2bd7f2fa4506b528da9d8d6f912ddc5422e Mon Sep 17 00:00:00 2001
From: dan <dan.abramov@gmail.com>
Date: Wed, 8 May 2024 03:34:35 +0100
Subject: [PATCH] Add session reducer tests (#3860)

---
 package.json                                |    2 +-
 src/state/session/__tests__/session-test.ts | 1643 +++++++++++++++++++
 src/state/session/reducer.ts                |    1 +
 3 files changed, 1645 insertions(+), 1 deletion(-)
 create mode 100644 src/state/session/__tests__/session-test.ts

diff --git a/package.json b/package.json
index 4a6bbf5a..26d6b061 100644
--- a/package.json
+++ b/package.json
@@ -290,7 +290,7 @@
       "\\.[jt]sx?$": "babel-jest"
     },
     "transformIgnorePatterns": [
-      "node_modules/(?!((jest-)?react-native|@react-native(-community)?)|expo(nent)?|@expo(nent)?/.*|@expo-google-fonts/.*|react-navigation|nanoid|@react-navigation/.*|@unimodules/.*|unimodules|sentry-expo|native-base|normalize-url|react-native-svg|@sentry/.*|sentry-expo|bcp-47-match)"
+      "node_modules/(?!((jest-)?react-native|@react-native(-community)?)|@discord|expo(nent)?|@expo(nent)?/.*|@expo-google-fonts/.*|react-navigation|nanoid|@react-navigation/.*|@unimodules/.*|unimodules|sentry-expo|native-base|normalize-url|react-native-svg|@sentry/.*|sentry-expo|bcp-47-match)"
     ],
     "modulePathIgnorePatterns": [
       "__tests__/.*/__mocks__",
diff --git a/src/state/session/__tests__/session-test.ts b/src/state/session/__tests__/session-test.ts
new file mode 100644
index 00000000..b1886ff8
--- /dev/null
+++ b/src/state/session/__tests__/session-test.ts
@@ -0,0 +1,1643 @@
+import {BskyAgent} from '@atproto/api'
+import {describe, expect, it, jest} from '@jest/globals'
+
+import {agentToSessionAccountOrThrow} from '../agent'
+import {Action, getInitialState, reducer, State} from '../reducer'
+
+jest.mock('jwt-decode', () => ({
+  jwtDecode(_token: string) {
+    return {}
+  },
+}))
+
+describe('session', () => {
+  it('can log in and out', () => {
+    let state = getInitialState([])
+    expect(printState(state)).toMatchInlineSnapshot(`
+      {
+        "accounts": [],
+        "currentAgentState": {
+          "agent": {
+            "service": "https://public.api.bsky.app/",
+          },
+          "did": undefined,
+        },
+        "needsPersist": false,
+      }
+    `)
+
+    const agent = new BskyAgent({service: 'https://alice.com'})
+    agent.session = {
+      did: 'alice-did',
+      handle: 'alice.test',
+      accessJwt: 'alice-access-jwt-1',
+      refreshJwt: 'alice-refresh-jwt-1',
+    }
+    state = run(state, [
+      {
+        type: 'switched-to-account',
+        newAgent: agent,
+        newAccount: agentToSessionAccountOrThrow(agent),
+      },
+    ])
+    expect(state.currentAgentState.did).toBe('alice-did')
+    expect(state.accounts.length).toBe(1)
+    expect(state.accounts[0].did).toBe('alice-did')
+    expect(state.accounts[0].accessJwt).toBe('alice-access-jwt-1')
+    expect(state.accounts[0].refreshJwt).toBe('alice-refresh-jwt-1')
+    expect(printState(state)).toMatchInlineSnapshot(`
+      {
+        "accounts": [
+          {
+            "accessJwt": "alice-access-jwt-1",
+            "deactivated": false,
+            "did": "alice-did",
+            "email": undefined,
+            "emailAuthFactor": false,
+            "emailConfirmed": false,
+            "handle": "alice.test",
+            "pdsUrl": undefined,
+            "refreshJwt": "alice-refresh-jwt-1",
+            "service": "https://alice.com/",
+          },
+        ],
+        "currentAgentState": {
+          "agent": {
+            "service": "https://alice.com/",
+          },
+          "did": "alice-did",
+        },
+        "needsPersist": true,
+      }
+    `)
+
+    state = run(state, [
+      {
+        type: 'logged-out',
+      },
+    ])
+    // Should keep the account but clear out the tokens.
+    expect(state.currentAgentState.did).toBe(undefined)
+    expect(state.accounts.length).toBe(1)
+    expect(state.accounts[0].did).toBe('alice-did')
+    expect(state.accounts[0].accessJwt).toBe(undefined)
+    expect(state.accounts[0].refreshJwt).toBe(undefined)
+    expect(printState(state)).toMatchInlineSnapshot(`
+      {
+        "accounts": [
+          {
+            "accessJwt": undefined,
+            "deactivated": false,
+            "did": "alice-did",
+            "email": undefined,
+            "emailAuthFactor": false,
+            "emailConfirmed": false,
+            "handle": "alice.test",
+            "pdsUrl": undefined,
+            "refreshJwt": undefined,
+            "service": "https://alice.com/",
+          },
+        ],
+        "currentAgentState": {
+          "agent": {
+            "service": "https://public.api.bsky.app/",
+          },
+          "did": undefined,
+        },
+        "needsPersist": true,
+      }
+    `)
+  })
+
+  it('switches to the latest account, stores all of them', () => {
+    let state = getInitialState([])
+
+    const agent1 = new BskyAgent({service: 'https://alice.com'})
+    agent1.session = {
+      did: 'alice-did',
+      handle: 'alice.test',
+      accessJwt: 'alice-access-jwt-1',
+      refreshJwt: 'alice-refresh-jwt-1',
+    }
+    state = run(state, [
+      {
+        // Switch to Alice.
+        type: 'switched-to-account',
+        newAgent: agent1,
+        newAccount: agentToSessionAccountOrThrow(agent1),
+      },
+    ])
+    expect(state.accounts.length).toBe(1)
+    expect(state.accounts[0].did).toBe('alice-did')
+    expect(state.currentAgentState.did).toBe('alice-did')
+    expect(state.currentAgentState.agent).toBe(agent1)
+    expect(printState(state)).toMatchInlineSnapshot(`
+      {
+        "accounts": [
+          {
+            "accessJwt": "alice-access-jwt-1",
+            "deactivated": false,
+            "did": "alice-did",
+            "email": undefined,
+            "emailAuthFactor": false,
+            "emailConfirmed": false,
+            "handle": "alice.test",
+            "pdsUrl": undefined,
+            "refreshJwt": "alice-refresh-jwt-1",
+            "service": "https://alice.com/",
+          },
+        ],
+        "currentAgentState": {
+          "agent": {
+            "service": "https://alice.com/",
+          },
+          "did": "alice-did",
+        },
+        "needsPersist": true,
+      }
+    `)
+
+    const agent2 = new BskyAgent({service: 'https://bob.com'})
+    agent2.session = {
+      did: 'bob-did',
+      handle: 'bob.test',
+      accessJwt: 'bob-access-jwt-1',
+      refreshJwt: 'bob-refresh-jwt-1',
+    }
+    state = run(state, [
+      {
+        // Switch to Bob.
+        type: 'switched-to-account',
+        newAgent: agent2,
+        newAccount: agentToSessionAccountOrThrow(agent2),
+      },
+    ])
+    expect(state.accounts.length).toBe(2)
+    // Bob should float upwards.
+    expect(state.accounts[0].did).toBe('bob-did')
+    expect(state.accounts[1].did).toBe('alice-did')
+    expect(state.currentAgentState.did).toBe('bob-did')
+    expect(state.currentAgentState.agent).toBe(agent2)
+    expect(printState(state)).toMatchInlineSnapshot(`
+      {
+        "accounts": [
+          {
+            "accessJwt": "bob-access-jwt-1",
+            "deactivated": false,
+            "did": "bob-did",
+            "email": undefined,
+            "emailAuthFactor": false,
+            "emailConfirmed": false,
+            "handle": "bob.test",
+            "pdsUrl": undefined,
+            "refreshJwt": "bob-refresh-jwt-1",
+            "service": "https://bob.com/",
+          },
+          {
+            "accessJwt": "alice-access-jwt-1",
+            "deactivated": false,
+            "did": "alice-did",
+            "email": undefined,
+            "emailAuthFactor": false,
+            "emailConfirmed": false,
+            "handle": "alice.test",
+            "pdsUrl": undefined,
+            "refreshJwt": "alice-refresh-jwt-1",
+            "service": "https://alice.com/",
+          },
+        ],
+        "currentAgentState": {
+          "agent": {
+            "service": "https://bob.com/",
+          },
+          "did": "bob-did",
+        },
+        "needsPersist": true,
+      }
+    `)
+
+    const agent3 = new BskyAgent({service: 'https://alice.com'})
+    agent3.session = {
+      did: 'alice-did',
+      handle: 'alice-updated.test',
+      accessJwt: 'alice-access-jwt-2',
+      refreshJwt: 'alice-refresh-jwt-2',
+    }
+    state = run(state, [
+      {
+        // Switch back to Alice.
+        type: 'switched-to-account',
+        newAgent: agent3,
+        newAccount: agentToSessionAccountOrThrow(agent3),
+      },
+    ])
+    expect(state.accounts.length).toBe(2)
+    // Alice should float upwards.
+    expect(state.accounts[0].did).toBe('alice-did')
+    expect(state.accounts[0].handle).toBe('alice-updated.test')
+    expect(state.currentAgentState.did).toBe('alice-did')
+    expect(state.currentAgentState.agent).toBe(agent3)
+    expect(printState(state)).toMatchInlineSnapshot(`
+      {
+        "accounts": [
+          {
+            "accessJwt": "alice-access-jwt-2",
+            "deactivated": false,
+            "did": "alice-did",
+            "email": undefined,
+            "emailAuthFactor": false,
+            "emailConfirmed": false,
+            "handle": "alice-updated.test",
+            "pdsUrl": undefined,
+            "refreshJwt": "alice-refresh-jwt-2",
+            "service": "https://alice.com/",
+          },
+          {
+            "accessJwt": "bob-access-jwt-1",
+            "deactivated": false,
+            "did": "bob-did",
+            "email": undefined,
+            "emailAuthFactor": false,
+            "emailConfirmed": false,
+            "handle": "bob.test",
+            "pdsUrl": undefined,
+            "refreshJwt": "bob-refresh-jwt-1",
+            "service": "https://bob.com/",
+          },
+        ],
+        "currentAgentState": {
+          "agent": {
+            "service": "https://alice.com/",
+          },
+          "did": "alice-did",
+        },
+        "needsPersist": true,
+      }
+    `)
+
+    const agent4 = new BskyAgent({service: 'https://jay.com'})
+    agent4.session = {
+      did: 'jay-did',
+      handle: 'jay.test',
+      accessJwt: 'jay-access-jwt-1',
+      refreshJwt: 'jay-refresh-jwt-1',
+    }
+    state = run(state, [
+      {
+        // Switch to Jay.
+        type: 'switched-to-account',
+        newAgent: agent4,
+        newAccount: agentToSessionAccountOrThrow(agent4),
+      },
+    ])
+    expect(state.accounts.length).toBe(3)
+    expect(state.accounts[0].did).toBe('jay-did')
+    expect(state.currentAgentState.did).toBe('jay-did')
+    expect(state.currentAgentState.agent).toBe(agent4)
+    expect(printState(state)).toMatchInlineSnapshot(`
+      {
+        "accounts": [
+          {
+            "accessJwt": "jay-access-jwt-1",
+            "deactivated": false,
+            "did": "jay-did",
+            "email": undefined,
+            "emailAuthFactor": false,
+            "emailConfirmed": false,
+            "handle": "jay.test",
+            "pdsUrl": undefined,
+            "refreshJwt": "jay-refresh-jwt-1",
+            "service": "https://jay.com/",
+          },
+          {
+            "accessJwt": "alice-access-jwt-2",
+            "deactivated": false,
+            "did": "alice-did",
+            "email": undefined,
+            "emailAuthFactor": false,
+            "emailConfirmed": false,
+            "handle": "alice-updated.test",
+            "pdsUrl": undefined,
+            "refreshJwt": "alice-refresh-jwt-2",
+            "service": "https://alice.com/",
+          },
+          {
+            "accessJwt": "bob-access-jwt-1",
+            "deactivated": false,
+            "did": "bob-did",
+            "email": undefined,
+            "emailAuthFactor": false,
+            "emailConfirmed": false,
+            "handle": "bob.test",
+            "pdsUrl": undefined,
+            "refreshJwt": "bob-refresh-jwt-1",
+            "service": "https://bob.com/",
+          },
+        ],
+        "currentAgentState": {
+          "agent": {
+            "service": "https://jay.com/",
+          },
+          "did": "jay-did",
+        },
+        "needsPersist": true,
+      }
+    `)
+
+    state = run(state, [
+      {
+        // Log everyone out.
+        type: 'logged-out',
+      },
+    ])
+    expect(state.accounts.length).toBe(3)
+    expect(state.currentAgentState.did).toBe(undefined)
+    // All tokens should be gone.
+    expect(state.accounts[0].accessJwt).toBe(undefined)
+    expect(state.accounts[0].refreshJwt).toBe(undefined)
+    expect(state.accounts[1].accessJwt).toBe(undefined)
+    expect(state.accounts[1].refreshJwt).toBe(undefined)
+    expect(state.accounts[2].accessJwt).toBe(undefined)
+    expect(state.accounts[2].refreshJwt).toBe(undefined)
+    expect(printState(state)).toMatchInlineSnapshot(`
+      {
+        "accounts": [
+          {
+            "accessJwt": undefined,
+            "deactivated": false,
+            "did": "jay-did",
+            "email": undefined,
+            "emailAuthFactor": false,
+            "emailConfirmed": false,
+            "handle": "jay.test",
+            "pdsUrl": undefined,
+            "refreshJwt": undefined,
+            "service": "https://jay.com/",
+          },
+          {
+            "accessJwt": undefined,
+            "deactivated": false,
+            "did": "alice-did",
+            "email": undefined,
+            "emailAuthFactor": false,
+            "emailConfirmed": false,
+            "handle": "alice-updated.test",
+            "pdsUrl": undefined,
+            "refreshJwt": undefined,
+            "service": "https://alice.com/",
+          },
+          {
+            "accessJwt": undefined,
+            "deactivated": false,
+            "did": "bob-did",
+            "email": undefined,
+            "emailAuthFactor": false,
+            "emailConfirmed": false,
+            "handle": "bob.test",
+            "pdsUrl": undefined,
+            "refreshJwt": undefined,
+            "service": "https://bob.com/",
+          },
+        ],
+        "currentAgentState": {
+          "agent": {
+            "service": "https://public.api.bsky.app/",
+          },
+          "did": undefined,
+        },
+        "needsPersist": true,
+      }
+    `)
+  })
+
+  it('can log back in after logging out', () => {
+    let state = getInitialState([])
+
+    const agent1 = new BskyAgent({service: 'https://alice.com'})
+    agent1.session = {
+      did: 'alice-did',
+      handle: 'alice.test',
+      accessJwt: 'alice-access-jwt-1',
+      refreshJwt: 'alice-refresh-jwt-1',
+    }
+    state = run(state, [
+      {
+        type: 'switched-to-account',
+        newAgent: agent1,
+        newAccount: agentToSessionAccountOrThrow(agent1),
+      },
+    ])
+    expect(state.accounts.length).toBe(1)
+    expect(state.accounts[0].accessJwt).toBe('alice-access-jwt-1')
+    expect(state.accounts[0].refreshJwt).toBe('alice-refresh-jwt-1')
+    expect(state.currentAgentState.did).toBe('alice-did')
+
+    state = run(state, [
+      {
+        type: 'logged-out',
+      },
+    ])
+    expect(state.accounts.length).toBe(1)
+    expect(state.accounts[0].accessJwt).toBe(undefined)
+    expect(state.accounts[0].refreshJwt).toBe(undefined)
+    expect(state.currentAgentState.did).toBe(undefined)
+    expect(printState(state)).toMatchInlineSnapshot(`
+      {
+        "accounts": [
+          {
+            "accessJwt": undefined,
+            "deactivated": false,
+            "did": "alice-did",
+            "email": undefined,
+            "emailAuthFactor": false,
+            "emailConfirmed": false,
+            "handle": "alice.test",
+            "pdsUrl": undefined,
+            "refreshJwt": undefined,
+            "service": "https://alice.com/",
+          },
+        ],
+        "currentAgentState": {
+          "agent": {
+            "service": "https://public.api.bsky.app/",
+          },
+          "did": undefined,
+        },
+        "needsPersist": true,
+      }
+    `)
+
+    const agent2 = new BskyAgent({service: 'https://alice.com'})
+    agent2.session = {
+      did: 'alice-did',
+      handle: 'alice.test',
+      accessJwt: 'alice-access-jwt-2',
+      refreshJwt: 'alice-refresh-jwt-2',
+    }
+    state = run(state, [
+      {
+        type: 'switched-to-account',
+        newAgent: agent2,
+        newAccount: agentToSessionAccountOrThrow(agent2),
+      },
+    ])
+    expect(state.accounts.length).toBe(1)
+    expect(state.accounts[0].accessJwt).toBe('alice-access-jwt-2')
+    expect(state.accounts[0].refreshJwt).toBe('alice-refresh-jwt-2')
+    expect(state.currentAgentState.did).toBe('alice-did')
+    expect(printState(state)).toMatchInlineSnapshot(`
+      {
+        "accounts": [
+          {
+            "accessJwt": "alice-access-jwt-2",
+            "deactivated": false,
+            "did": "alice-did",
+            "email": undefined,
+            "emailAuthFactor": false,
+            "emailConfirmed": false,
+            "handle": "alice.test",
+            "pdsUrl": undefined,
+            "refreshJwt": "alice-refresh-jwt-2",
+            "service": "https://alice.com/",
+          },
+        ],
+        "currentAgentState": {
+          "agent": {
+            "service": "https://alice.com/",
+          },
+          "did": "alice-did",
+        },
+        "needsPersist": true,
+      }
+    `)
+  })
+
+  it('can remove active account', () => {
+    let state = getInitialState([])
+
+    const agent1 = new BskyAgent({service: 'https://alice.com'})
+    agent1.session = {
+      did: 'alice-did',
+      handle: 'alice.test',
+      accessJwt: 'alice-access-jwt-1',
+      refreshJwt: 'alice-refresh-jwt-1',
+    }
+    state = run(state, [
+      {
+        type: 'switched-to-account',
+        newAgent: agent1,
+        newAccount: agentToSessionAccountOrThrow(agent1),
+      },
+    ])
+    expect(state.accounts.length).toBe(1)
+    expect(state.accounts[0].accessJwt).toBe('alice-access-jwt-1')
+    expect(state.accounts[0].refreshJwt).toBe('alice-refresh-jwt-1')
+    expect(state.currentAgentState.did).toBe('alice-did')
+
+    state = run(state, [
+      {
+        type: 'removed-account',
+        accountDid: 'alice-did',
+      },
+    ])
+    expect(state.accounts.length).toBe(0)
+    expect(state.currentAgentState.did).toBe(undefined)
+    expect(printState(state)).toMatchInlineSnapshot(`
+      {
+        "accounts": [],
+        "currentAgentState": {
+          "agent": {
+            "service": "https://public.api.bsky.app/",
+          },
+          "did": undefined,
+        },
+        "needsPersist": true,
+      }
+    `)
+  })
+
+  it('can remove inactive account', () => {
+    let state = getInitialState([])
+
+    const agent1 = new BskyAgent({service: 'https://alice.com'})
+    agent1.session = {
+      did: 'alice-did',
+      handle: 'alice.test',
+      accessJwt: 'alice-access-jwt-1',
+      refreshJwt: 'alice-refresh-jwt-1',
+    }
+    const agent2 = new BskyAgent({service: 'https://bob.com'})
+    agent2.session = {
+      did: 'bob-did',
+      handle: 'bob.test',
+      accessJwt: 'bob-access-jwt-1',
+      refreshJwt: 'bob-refresh-jwt-1',
+    }
+    state = run(state, [
+      {
+        type: 'switched-to-account',
+        newAgent: agent1,
+        newAccount: agentToSessionAccountOrThrow(agent1),
+      },
+      {
+        type: 'switched-to-account',
+        newAgent: agent2,
+        newAccount: agentToSessionAccountOrThrow(agent2),
+      },
+    ])
+    expect(state.accounts.length).toBe(2)
+    expect(state.currentAgentState.did).toBe('bob-did')
+
+    state = run(state, [
+      {
+        type: 'removed-account',
+        accountDid: 'alice-did',
+      },
+    ])
+    expect(state.accounts.length).toBe(1)
+    expect(state.currentAgentState.did).toBe('bob-did')
+    expect(printState(state)).toMatchInlineSnapshot(`
+      {
+        "accounts": [
+          {
+            "accessJwt": "bob-access-jwt-1",
+            "deactivated": false,
+            "did": "bob-did",
+            "email": undefined,
+            "emailAuthFactor": false,
+            "emailConfirmed": false,
+            "handle": "bob.test",
+            "pdsUrl": undefined,
+            "refreshJwt": "bob-refresh-jwt-1",
+            "service": "https://bob.com/",
+          },
+        ],
+        "currentAgentState": {
+          "agent": {
+            "service": "https://bob.com/",
+          },
+          "did": "bob-did",
+        },
+        "needsPersist": true,
+      }
+    `)
+
+    state = run(state, [
+      {
+        type: 'removed-account',
+        accountDid: 'bob-did',
+      },
+    ])
+    expect(state.accounts.length).toBe(0)
+    expect(state.currentAgentState.did).toBe(undefined)
+  })
+
+  it('updates stored account with refreshed tokens', () => {
+    let state = getInitialState([])
+
+    const agent1 = new BskyAgent({service: 'https://alice.com'})
+    agent1.session = {
+      did: 'alice-did',
+      handle: 'alice.test',
+      accessJwt: 'alice-access-jwt-1',
+      refreshJwt: 'alice-refresh-jwt-1',
+    }
+    state = run(state, [
+      {
+        type: 'switched-to-account',
+        newAgent: agent1,
+        newAccount: agentToSessionAccountOrThrow(agent1),
+      },
+    ])
+    expect(state.accounts.length).toBe(1)
+    expect(state.currentAgentState.did).toBe('alice-did')
+
+    agent1.session = {
+      did: 'alice-did',
+      handle: 'alice-updated.test',
+      accessJwt: 'alice-access-jwt-2',
+      refreshJwt: 'alice-refresh-jwt-2',
+      email: 'alice@foo.bar',
+      emailAuthFactor: false,
+      emailConfirmed: false,
+    }
+    state = run(state, [
+      {
+        type: 'received-agent-event',
+        accountDid: 'alice-did',
+        agent: agent1,
+        refreshedAccount: agentToSessionAccountOrThrow(agent1),
+        sessionEvent: 'update',
+      },
+    ])
+    expect(state.accounts.length).toBe(1)
+    expect(state.accounts[0].email).toBe('alice@foo.bar')
+    expect(state.accounts[0].handle).toBe('alice-updated.test')
+    expect(state.accounts[0].accessJwt).toBe('alice-access-jwt-2')
+    expect(state.accounts[0].refreshJwt).toBe('alice-refresh-jwt-2')
+    expect(state.currentAgentState.did).toBe('alice-did')
+    expect(printState(state)).toMatchInlineSnapshot(`
+      {
+        "accounts": [
+          {
+            "accessJwt": "alice-access-jwt-2",
+            "deactivated": false,
+            "did": "alice-did",
+            "email": "alice@foo.bar",
+            "emailAuthFactor": false,
+            "emailConfirmed": false,
+            "handle": "alice-updated.test",
+            "pdsUrl": undefined,
+            "refreshJwt": "alice-refresh-jwt-2",
+            "service": "https://alice.com/",
+          },
+        ],
+        "currentAgentState": {
+          "agent": {
+            "service": "https://alice.com/",
+          },
+          "did": "alice-did",
+        },
+        "needsPersist": true,
+      }
+    `)
+
+    agent1.session = {
+      did: 'alice-did',
+      handle: 'alice-updated.test',
+      accessJwt: 'alice-access-jwt-3',
+      refreshJwt: 'alice-refresh-jwt-3',
+      email: 'alice@foo.baz',
+      emailAuthFactor: true,
+      emailConfirmed: true,
+    }
+    state = run(state, [
+      {
+        type: 'received-agent-event',
+        accountDid: 'alice-did',
+        agent: agent1,
+        refreshedAccount: agentToSessionAccountOrThrow(agent1),
+        sessionEvent: 'update',
+      },
+    ])
+    expect(state.accounts.length).toBe(1)
+    expect(state.accounts[0].email).toBe('alice@foo.baz')
+    expect(state.accounts[0].handle).toBe('alice-updated.test')
+    expect(state.accounts[0].accessJwt).toBe('alice-access-jwt-3')
+    expect(state.accounts[0].refreshJwt).toBe('alice-refresh-jwt-3')
+    expect(state.currentAgentState.did).toBe('alice-did')
+    expect(printState(state)).toMatchInlineSnapshot(`
+      {
+        "accounts": [
+          {
+            "accessJwt": "alice-access-jwt-3",
+            "deactivated": false,
+            "did": "alice-did",
+            "email": "alice@foo.baz",
+            "emailAuthFactor": true,
+            "emailConfirmed": true,
+            "handle": "alice-updated.test",
+            "pdsUrl": undefined,
+            "refreshJwt": "alice-refresh-jwt-3",
+            "service": "https://alice.com/",
+          },
+        ],
+        "currentAgentState": {
+          "agent": {
+            "service": "https://alice.com/",
+          },
+          "did": "alice-did",
+        },
+        "needsPersist": true,
+      }
+    `)
+
+    agent1.session = {
+      did: 'alice-did',
+      handle: 'alice-updated.test',
+      accessJwt: 'alice-access-jwt-4',
+      refreshJwt: 'alice-refresh-jwt-4',
+      email: 'alice@foo.baz',
+      emailAuthFactor: false,
+      emailConfirmed: false,
+    }
+    state = run(state, [
+      {
+        type: 'received-agent-event',
+        accountDid: 'alice-did',
+        agent: agent1,
+        refreshedAccount: agentToSessionAccountOrThrow(agent1),
+        sessionEvent: 'update',
+      },
+    ])
+    expect(state.accounts.length).toBe(1)
+    expect(state.accounts[0].email).toBe('alice@foo.baz')
+    expect(state.accounts[0].handle).toBe('alice-updated.test')
+    expect(state.accounts[0].accessJwt).toBe('alice-access-jwt-4')
+    expect(state.accounts[0].refreshJwt).toBe('alice-refresh-jwt-4')
+    expect(state.currentAgentState.did).toBe('alice-did')
+    expect(printState(state)).toMatchInlineSnapshot(`
+      {
+        "accounts": [
+          {
+            "accessJwt": "alice-access-jwt-4",
+            "deactivated": false,
+            "did": "alice-did",
+            "email": "alice@foo.baz",
+            "emailAuthFactor": false,
+            "emailConfirmed": false,
+            "handle": "alice-updated.test",
+            "pdsUrl": undefined,
+            "refreshJwt": "alice-refresh-jwt-4",
+            "service": "https://alice.com/",
+          },
+        ],
+        "currentAgentState": {
+          "agent": {
+            "service": "https://alice.com/",
+          },
+          "did": "alice-did",
+        },
+        "needsPersist": true,
+      }
+    `)
+  })
+
+  it('bails out of update on identical objects', () => {
+    let state = getInitialState([])
+
+    const agent1 = new BskyAgent({service: 'https://alice.com'})
+    agent1.session = {
+      did: 'alice-did',
+      handle: 'alice.test',
+      accessJwt: 'alice-access-jwt-1',
+      refreshJwt: 'alice-refresh-jwt-1',
+    }
+    state = run(state, [
+      {
+        type: 'switched-to-account',
+        newAgent: agent1,
+        newAccount: agentToSessionAccountOrThrow(agent1),
+      },
+    ])
+    expect(state.accounts.length).toBe(1)
+    expect(state.currentAgentState.did).toBe('alice-did')
+
+    agent1.session = {
+      did: 'alice-did',
+      handle: 'alice-updated.test',
+      accessJwt: 'alice-access-jwt-2',
+      refreshJwt: 'alice-refresh-jwt-2',
+    }
+    state = run(state, [
+      {
+        type: 'received-agent-event',
+        accountDid: 'alice-did',
+        agent: agent1,
+        refreshedAccount: agentToSessionAccountOrThrow(agent1),
+        sessionEvent: 'update',
+      },
+    ])
+    expect(state.accounts.length).toBe(1)
+    expect(state.accounts[0].accessJwt).toBe('alice-access-jwt-2')
+
+    const lastState = state
+    state = run(state, [
+      {
+        type: 'received-agent-event',
+        accountDid: 'alice-did',
+        agent: agent1,
+        refreshedAccount: agentToSessionAccountOrThrow(agent1),
+        sessionEvent: 'update',
+      },
+    ])
+    expect(lastState === state).toBe(true)
+
+    agent1.session = {
+      did: 'alice-did',
+      handle: 'alice-updated.test',
+      accessJwt: 'alice-access-jwt-3',
+      refreshJwt: 'alice-refresh-jwt-3',
+    }
+    state = run(state, [
+      {
+        type: 'received-agent-event',
+        accountDid: 'alice-did',
+        agent: agent1,
+        refreshedAccount: agentToSessionAccountOrThrow(agent1),
+        sessionEvent: 'update',
+      },
+    ])
+    expect(state.accounts.length).toBe(1)
+    expect(state.accounts[0].accessJwt).toBe('alice-access-jwt-3')
+  })
+
+  it('ignores updates from a stale agent', () => {
+    let state = getInitialState([])
+
+    const agent1 = new BskyAgent({service: 'https://alice.com'})
+    agent1.session = {
+      did: 'alice-did',
+      handle: 'alice.test',
+      accessJwt: 'alice-access-jwt-1',
+      refreshJwt: 'alice-refresh-jwt-1',
+    }
+
+    const agent2 = new BskyAgent({service: 'https://bob.com'})
+    agent2.session = {
+      did: 'bob-did',
+      handle: 'bob.test',
+      accessJwt: 'bob-access-jwt-1',
+      refreshJwt: 'bob-refresh-jwt-1',
+    }
+
+    state = run(state, [
+      {
+        // Switch to Alice.
+        type: 'switched-to-account',
+        newAgent: agent1,
+        newAccount: agentToSessionAccountOrThrow(agent1),
+      },
+      {
+        // Switch to Bob.
+        type: 'switched-to-account',
+        newAgent: agent2,
+        newAccount: agentToSessionAccountOrThrow(agent2),
+      },
+    ])
+    expect(state.accounts.length).toBe(2)
+    expect(state.currentAgentState.did).toBe('bob-did')
+
+    agent1.session = {
+      did: 'alice-did',
+      handle: 'alice-updated.test',
+      accessJwt: 'alice-access-jwt-2',
+      refreshJwt: 'alice-refresh-jwt-2',
+      email: 'alice@foo.bar',
+      emailAuthFactor: false,
+      emailConfirmed: false,
+    }
+    state = run(state, [
+      {
+        type: 'received-agent-event',
+        accountDid: 'alice-did',
+        agent: agent1,
+        refreshedAccount: agentToSessionAccountOrThrow(agent1),
+        sessionEvent: 'update',
+      },
+    ])
+    expect(state.accounts.length).toBe(2)
+    expect(state.accounts[1].did).toBe('alice-did')
+    // Should retain the old values because Alice is not active.
+    expect(state.accounts[1].handle).toBe('alice.test')
+    expect(state.accounts[1].accessJwt).toBe('alice-access-jwt-1')
+    expect(state.accounts[1].refreshJwt).toBe('alice-refresh-jwt-1')
+    expect(printState(state)).toMatchInlineSnapshot(`
+      {
+        "accounts": [
+          {
+            "accessJwt": "bob-access-jwt-1",
+            "deactivated": false,
+            "did": "bob-did",
+            "email": undefined,
+            "emailAuthFactor": false,
+            "emailConfirmed": false,
+            "handle": "bob.test",
+            "pdsUrl": undefined,
+            "refreshJwt": "bob-refresh-jwt-1",
+            "service": "https://bob.com/",
+          },
+          {
+            "accessJwt": "alice-access-jwt-1",
+            "deactivated": false,
+            "did": "alice-did",
+            "email": undefined,
+            "emailAuthFactor": false,
+            "emailConfirmed": false,
+            "handle": "alice.test",
+            "pdsUrl": undefined,
+            "refreshJwt": "alice-refresh-jwt-1",
+            "service": "https://alice.com/",
+          },
+        ],
+        "currentAgentState": {
+          "agent": {
+            "service": "https://bob.com/",
+          },
+          "did": "bob-did",
+        },
+        "needsPersist": true,
+      }
+    `)
+
+    agent2.session = {
+      did: 'bob-did',
+      handle: 'bob-updated.test',
+      accessJwt: 'bob-access-jwt-2',
+      refreshJwt: 'bob-refresh-jwt-2',
+    }
+    state = run(state, [
+      {
+        // Update Bob.
+        type: 'received-agent-event',
+        accountDid: 'bob-did',
+        agent: agent2,
+        refreshedAccount: agentToSessionAccountOrThrow(agent2),
+        sessionEvent: 'update',
+      },
+    ])
+    expect(state.accounts.length).toBe(2)
+    expect(state.accounts[0].did).toBe('bob-did')
+    // Should update the values because Bob is active.
+    expect(state.accounts[0].handle).toBe('bob-updated.test')
+    expect(state.accounts[0].accessJwt).toBe('bob-access-jwt-2')
+    expect(state.accounts[0].refreshJwt).toBe('bob-refresh-jwt-2')
+    expect(printState(state)).toMatchInlineSnapshot(`
+      {
+        "accounts": [
+          {
+            "accessJwt": "bob-access-jwt-2",
+            "deactivated": false,
+            "did": "bob-did",
+            "email": undefined,
+            "emailAuthFactor": false,
+            "emailConfirmed": false,
+            "handle": "bob-updated.test",
+            "pdsUrl": undefined,
+            "refreshJwt": "bob-refresh-jwt-2",
+            "service": "https://bob.com/",
+          },
+          {
+            "accessJwt": "alice-access-jwt-1",
+            "deactivated": false,
+            "did": "alice-did",
+            "email": undefined,
+            "emailAuthFactor": false,
+            "emailConfirmed": false,
+            "handle": "alice.test",
+            "pdsUrl": undefined,
+            "refreshJwt": "alice-refresh-jwt-1",
+            "service": "https://alice.com/",
+          },
+        ],
+        "currentAgentState": {
+          "agent": {
+            "service": "https://bob.com/",
+          },
+          "did": "bob-did",
+        },
+        "needsPersist": true,
+      }
+    `)
+
+    // Ignore other events for inactive agent too.
+    const lastState = state
+    agent1.session = undefined
+    state = run(state, [
+      {
+        type: 'received-agent-event',
+        accountDid: 'alice-did',
+        agent: agent1,
+        refreshedAccount: undefined,
+        sessionEvent: 'network-error',
+      },
+    ])
+    expect(lastState === state).toBe(true)
+    state = run(state, [
+      {
+        type: 'received-agent-event',
+        accountDid: 'alice-did',
+        agent: agent1,
+        refreshedAccount: undefined,
+        sessionEvent: 'expired',
+      },
+    ])
+    expect(lastState === state).toBe(true)
+  })
+
+  it('ignores updates from a removed agent', () => {
+    let state = getInitialState([])
+
+    const agent1 = new BskyAgent({service: 'https://alice.com'})
+    agent1.session = {
+      did: 'alice-did',
+      handle: 'alice.test',
+      accessJwt: 'alice-access-jwt-1',
+      refreshJwt: 'alice-refresh-jwt-1',
+    }
+
+    const agent2 = new BskyAgent({service: 'https://bob.com'})
+    agent2.session = {
+      did: 'bob-did',
+      handle: 'bob.test',
+      accessJwt: 'bob-access-jwt-1',
+      refreshJwt: 'bob-refresh-jwt-1',
+    }
+
+    state = run(state, [
+      {
+        type: 'switched-to-account',
+        newAgent: agent1,
+        newAccount: agentToSessionAccountOrThrow(agent1),
+      },
+      {
+        type: 'switched-to-account',
+        newAgent: agent2,
+        newAccount: agentToSessionAccountOrThrow(agent2),
+      },
+      {
+        type: 'removed-account',
+        accountDid: 'alice-did',
+      },
+    ])
+    expect(state.accounts.length).toBe(1)
+    expect(state.currentAgentState.did).toBe('bob-did')
+
+    agent1.session = {
+      did: 'alice-did',
+      handle: 'alice.test',
+      accessJwt: 'alice-access-jwt-2',
+      refreshJwt: 'alice-refresh-jwt-2',
+    }
+    state = run(state, [
+      {
+        type: 'received-agent-event',
+        accountDid: 'alice-did',
+        agent: agent1,
+        refreshedAccount: agentToSessionAccountOrThrow(agent1),
+        sessionEvent: 'update',
+      },
+    ])
+    expect(state.accounts.length).toBe(1)
+    expect(state.accounts[0].did).toBe('bob-did')
+    expect(state.accounts[0].accessJwt).toBe('bob-access-jwt-1')
+    expect(state.currentAgentState.did).toBe('bob-did')
+  })
+
+  it('does soft logout on network error', () => {
+    let state = getInitialState([])
+
+    const agent1 = new BskyAgent({service: 'https://alice.com'})
+    agent1.session = {
+      did: 'alice-did',
+      handle: 'alice.test',
+      accessJwt: 'alice-access-jwt-1',
+      refreshJwt: 'alice-refresh-jwt-1',
+    }
+    state = run(state, [
+      {
+        // Switch to Alice.
+        type: 'switched-to-account',
+        newAgent: agent1,
+        newAccount: agentToSessionAccountOrThrow(agent1),
+      },
+    ])
+    expect(state.accounts.length).toBe(1)
+    expect(state.currentAgentState.did).toBe('alice-did')
+
+    agent1.session = undefined
+    state = run(state, [
+      {
+        type: 'received-agent-event',
+        accountDid: 'alice-did',
+        agent: agent1,
+        refreshedAccount: undefined,
+        sessionEvent: 'network-error',
+      },
+    ])
+    expect(state.accounts.length).toBe(1)
+    // Network error should reset current user but not reset the tokens.
+    // TODO: We might want to remove or change this behavior?
+    expect(state.accounts[0].accessJwt).toBe('alice-access-jwt-1')
+    expect(state.accounts[0].refreshJwt).toBe('alice-refresh-jwt-1')
+    expect(state.currentAgentState.did).toBe(undefined)
+    expect(printState(state)).toMatchInlineSnapshot(`
+      {
+        "accounts": [
+          {
+            "accessJwt": "alice-access-jwt-1",
+            "deactivated": false,
+            "did": "alice-did",
+            "email": undefined,
+            "emailAuthFactor": false,
+            "emailConfirmed": false,
+            "handle": "alice.test",
+            "pdsUrl": undefined,
+            "refreshJwt": "alice-refresh-jwt-1",
+            "service": "https://alice.com/",
+          },
+        ],
+        "currentAgentState": {
+          "agent": {
+            "service": "https://public.api.bsky.app/",
+          },
+          "did": undefined,
+        },
+        "needsPersist": true,
+      }
+    `)
+  })
+
+  it('resets tokens on expired event', () => {
+    let state = getInitialState([])
+
+    const agent1 = new BskyAgent({service: 'https://alice.com'})
+    agent1.session = {
+      did: 'alice-did',
+      handle: 'alice.test',
+      accessJwt: 'alice-access-jwt-1',
+      refreshJwt: 'alice-refresh-jwt-1',
+    }
+    state = run(state, [
+      {
+        type: 'switched-to-account',
+        newAgent: agent1,
+        newAccount: agentToSessionAccountOrThrow(agent1),
+      },
+    ])
+    expect(state.accounts.length).toBe(1)
+    expect(state.accounts[0].accessJwt).toBe('alice-access-jwt-1')
+    expect(state.currentAgentState.did).toBe('alice-did')
+
+    agent1.session = undefined
+    state = run(state, [
+      {
+        type: 'received-agent-event',
+        accountDid: 'alice-did',
+        agent: agent1,
+        refreshedAccount: undefined,
+        sessionEvent: 'expired',
+      },
+    ])
+    expect(state.accounts.length).toBe(1)
+    expect(state.accounts[0].accessJwt).toBe(undefined)
+    expect(state.accounts[0].refreshJwt).toBe(undefined)
+    expect(state.currentAgentState.did).toBe(undefined)
+    expect(printState(state)).toMatchInlineSnapshot(`
+      {
+        "accounts": [
+          {
+            "accessJwt": undefined,
+            "deactivated": false,
+            "did": "alice-did",
+            "email": undefined,
+            "emailAuthFactor": false,
+            "emailConfirmed": false,
+            "handle": "alice.test",
+            "pdsUrl": undefined,
+            "refreshJwt": undefined,
+            "service": "https://alice.com/",
+          },
+        ],
+        "currentAgentState": {
+          "agent": {
+            "service": "https://public.api.bsky.app/",
+          },
+          "did": undefined,
+        },
+        "needsPersist": true,
+      }
+    `)
+  })
+
+  it('resets tokens on created-failed event', () => {
+    let state = getInitialState([])
+
+    const agent1 = new BskyAgent({service: 'https://alice.com'})
+    agent1.session = {
+      did: 'alice-did',
+      handle: 'alice.test',
+      accessJwt: 'alice-access-jwt-1',
+      refreshJwt: 'alice-refresh-jwt-1',
+    }
+    state = run(state, [
+      {
+        type: 'switched-to-account',
+        newAgent: agent1,
+        newAccount: agentToSessionAccountOrThrow(agent1),
+      },
+    ])
+    expect(state.accounts.length).toBe(1)
+    expect(state.accounts[0].accessJwt).toBe('alice-access-jwt-1')
+    expect(state.currentAgentState.did).toBe('alice-did')
+
+    agent1.session = undefined
+    state = run(state, [
+      {
+        type: 'received-agent-event',
+        accountDid: 'alice-did',
+        agent: agent1,
+        refreshedAccount: undefined,
+        sessionEvent: 'create-failed',
+      },
+    ])
+    expect(state.accounts.length).toBe(1)
+    expect(state.accounts[0].accessJwt).toBe(undefined)
+    expect(state.accounts[0].refreshJwt).toBe(undefined)
+    expect(state.currentAgentState.did).toBe(undefined)
+    expect(printState(state)).toMatchInlineSnapshot(`
+      {
+        "accounts": [
+          {
+            "accessJwt": undefined,
+            "deactivated": false,
+            "did": "alice-did",
+            "email": undefined,
+            "emailAuthFactor": false,
+            "emailConfirmed": false,
+            "handle": "alice.test",
+            "pdsUrl": undefined,
+            "refreshJwt": undefined,
+            "service": "https://alice.com/",
+          },
+        ],
+        "currentAgentState": {
+          "agent": {
+            "service": "https://public.api.bsky.app/",
+          },
+          "did": undefined,
+        },
+        "needsPersist": true,
+      }
+    `)
+  })
+
+  it('updates current account', () => {
+    let state = getInitialState([])
+
+    const agent1 = new BskyAgent({service: 'https://alice.com'})
+    agent1.session = {
+      did: 'alice-did',
+      handle: 'alice.test',
+      accessJwt: 'alice-access-jwt-1',
+      refreshJwt: 'alice-refresh-jwt-1',
+    }
+    state = run(state, [
+      {
+        type: 'switched-to-account',
+        newAgent: agent1,
+        newAccount: agentToSessionAccountOrThrow(agent1),
+      },
+    ])
+    expect(state.accounts.length).toBe(1)
+    expect(state.accounts[0].accessJwt).toBe('alice-access-jwt-1')
+    expect(state.currentAgentState.did).toBe('alice-did')
+
+    state = run(state, [
+      {
+        type: 'updated-current-account',
+        updatedFields: {
+          email: 'alice@foo.bar',
+          emailConfirmed: false,
+        },
+      },
+    ])
+    expect(state.accounts.length).toBe(1)
+    expect(state.accounts[0].email).toBe('alice@foo.bar')
+    expect(state.accounts[0].emailConfirmed).toBe(false)
+    expect(state.currentAgentState.did).toBe('alice-did')
+    expect(printState(state)).toMatchInlineSnapshot(`
+      {
+        "accounts": [
+          {
+            "accessJwt": "alice-access-jwt-1",
+            "deactivated": false,
+            "did": "alice-did",
+            "email": "alice@foo.bar",
+            "emailAuthFactor": false,
+            "emailConfirmed": false,
+            "handle": "alice.test",
+            "pdsUrl": undefined,
+            "refreshJwt": "alice-refresh-jwt-1",
+            "service": "https://alice.com/",
+          },
+        ],
+        "currentAgentState": {
+          "agent": {
+            "service": "https://alice.com/",
+          },
+          "did": "alice-did",
+        },
+        "needsPersist": true,
+      }
+    `)
+
+    state = run(state, [
+      {
+        type: 'updated-current-account',
+        updatedFields: {
+          handle: 'alice-updated.test',
+        },
+      },
+    ])
+    expect(state.accounts.length).toBe(1)
+    expect(state.accounts[0].handle).toBe('alice-updated.test')
+    expect(state.currentAgentState.did).toBe('alice-did')
+    expect(printState(state)).toMatchInlineSnapshot(`
+      {
+        "accounts": [
+          {
+            "accessJwt": "alice-access-jwt-1",
+            "deactivated": false,
+            "did": "alice-did",
+            "email": "alice@foo.bar",
+            "emailAuthFactor": false,
+            "emailConfirmed": false,
+            "handle": "alice-updated.test",
+            "pdsUrl": undefined,
+            "refreshJwt": "alice-refresh-jwt-1",
+            "service": "https://alice.com/",
+          },
+        ],
+        "currentAgentState": {
+          "agent": {
+            "service": "https://alice.com/",
+          },
+          "did": "alice-did",
+        },
+        "needsPersist": true,
+      }
+    `)
+
+    const agent2 = new BskyAgent({service: 'https://bob.com'})
+    agent2.session = {
+      did: 'bob-did',
+      handle: 'bob.test',
+      accessJwt: 'bob-access-jwt-1',
+      refreshJwt: 'bob-refresh-jwt-1',
+    }
+    state = run(state, [
+      {
+        // Switch to Bob.
+        type: 'switched-to-account',
+        newAgent: agent2,
+        newAccount: agentToSessionAccountOrThrow(agent2),
+      },
+      {
+        // Update Bob.
+        type: 'updated-current-account',
+        updatedFields: {
+          handle: 'bob-updated.test',
+        },
+      },
+      {
+        // Switch back to Alice.
+        type: 'switched-to-account',
+        newAgent: agent1,
+        newAccount: agentToSessionAccountOrThrow(agent1),
+      },
+      {
+        // Update Alice.
+        type: 'updated-current-account',
+        updatedFields: {
+          handle: 'alice-updated-2.test',
+        },
+      },
+    ])
+    expect(printState(state)).toMatchInlineSnapshot(`
+      {
+        "accounts": [
+          {
+            "accessJwt": "alice-access-jwt-1",
+            "deactivated": false,
+            "did": "alice-did",
+            "email": undefined,
+            "emailAuthFactor": false,
+            "emailConfirmed": false,
+            "handle": "alice-updated-2.test",
+            "pdsUrl": undefined,
+            "refreshJwt": "alice-refresh-jwt-1",
+            "service": "https://alice.com/",
+          },
+          {
+            "accessJwt": "bob-access-jwt-1",
+            "deactivated": false,
+            "did": "bob-did",
+            "email": undefined,
+            "emailAuthFactor": false,
+            "emailConfirmed": false,
+            "handle": "bob-updated.test",
+            "pdsUrl": undefined,
+            "refreshJwt": "bob-refresh-jwt-1",
+            "service": "https://bob.com/",
+          },
+        ],
+        "currentAgentState": {
+          "agent": {
+            "service": "https://alice.com/",
+          },
+          "did": "alice-did",
+        },
+        "needsPersist": true,
+      }
+    `)
+  })
+
+  it('replaces local accounts with synced accounts', () => {
+    let state = getInitialState([])
+
+    const agent1 = new BskyAgent({service: 'https://alice.com'})
+    agent1.session = {
+      did: 'alice-did',
+      handle: 'alice.test',
+      accessJwt: 'alice-access-jwt-1',
+      refreshJwt: 'alice-refresh-jwt-1',
+    }
+    const agent2 = new BskyAgent({service: 'https://bob.com'})
+    agent2.session = {
+      did: 'bob-did',
+      handle: 'bob.test',
+      accessJwt: 'bob-access-jwt-1',
+      refreshJwt: 'bob-refresh-jwt-1',
+    }
+    state = run(state, [
+      {
+        type: 'switched-to-account',
+        newAgent: agent1,
+        newAccount: agentToSessionAccountOrThrow(agent1),
+      },
+      {
+        type: 'switched-to-account',
+        newAgent: agent2,
+        newAccount: agentToSessionAccountOrThrow(agent2),
+      },
+    ])
+    expect(state.accounts.length).toBe(2)
+    expect(state.currentAgentState.did).toBe('bob-did')
+
+    const anotherTabAgent1 = new BskyAgent({service: 'https://jay.com'})
+    anotherTabAgent1.session = {
+      did: 'jay-did',
+      handle: 'jay.test',
+      accessJwt: 'jay-access-jwt-1',
+      refreshJwt: 'jay-refresh-jwt-1',
+    }
+    const anotherTabAgent2 = new BskyAgent({service: 'https://alice.com'})
+    anotherTabAgent2.session = {
+      did: 'bob-did',
+      handle: 'bob.test',
+      accessJwt: 'bob-access-jwt-2',
+      refreshJwt: 'bob-refresh-jwt-2',
+    }
+    state = run(state, [
+      {
+        type: 'synced-accounts',
+        syncedAccounts: [
+          agentToSessionAccountOrThrow(anotherTabAgent1),
+          agentToSessionAccountOrThrow(anotherTabAgent2),
+        ],
+        syncedCurrentDid: 'bob-did',
+      },
+    ])
+    expect(state.accounts.length).toBe(2)
+    expect(state.accounts[0].did).toBe('jay-did')
+    expect(state.accounts[1].did).toBe('bob-did')
+    expect(state.accounts[1].accessJwt).toBe('bob-access-jwt-2')
+    // Keep Bob logged in.
+    // (We patch up agent.session outside the reducer for this to work.)
+    expect(state.currentAgentState.did).toBe('bob-did')
+    expect(state.needsPersist).toBe(false)
+    expect(printState(state)).toMatchInlineSnapshot(`
+      {
+        "accounts": [
+          {
+            "accessJwt": "jay-access-jwt-1",
+            "deactivated": false,
+            "did": "jay-did",
+            "email": undefined,
+            "emailAuthFactor": false,
+            "emailConfirmed": false,
+            "handle": "jay.test",
+            "pdsUrl": undefined,
+            "refreshJwt": "jay-refresh-jwt-1",
+            "service": "https://jay.com/",
+          },
+          {
+            "accessJwt": "bob-access-jwt-2",
+            "deactivated": false,
+            "did": "bob-did",
+            "email": undefined,
+            "emailAuthFactor": false,
+            "emailConfirmed": false,
+            "handle": "bob.test",
+            "pdsUrl": undefined,
+            "refreshJwt": "bob-refresh-jwt-2",
+            "service": "https://alice.com/",
+          },
+        ],
+        "currentAgentState": {
+          "agent": {
+            "service": "https://bob.com/",
+          },
+          "did": "bob-did",
+        },
+        "needsPersist": false,
+      }
+    `)
+
+    const anotherTabAgent3 = new BskyAgent({service: 'https://clarence.com'})
+    anotherTabAgent3.session = {
+      did: 'clarence-did',
+      handle: 'clarence.test',
+      accessJwt: 'clarence-access-jwt-2',
+      refreshJwt: 'clarence-refresh-jwt-2',
+    }
+    state = run(state, [
+      {
+        type: 'synced-accounts',
+        syncedAccounts: [agentToSessionAccountOrThrow(anotherTabAgent3)],
+        syncedCurrentDid: 'clarence-did',
+      },
+    ])
+    expect(state.accounts.length).toBe(1)
+    expect(state.accounts[0].did).toBe('clarence-did')
+    // Log out because we have no matching user.
+    // (In practice, we'll resume this session outside the reducer.)
+    expect(state.currentAgentState.did).toBe(undefined)
+    expect(state.needsPersist).toBe(false)
+    expect(printState(state)).toMatchInlineSnapshot(`
+      {
+        "accounts": [
+          {
+            "accessJwt": "clarence-access-jwt-2",
+            "deactivated": false,
+            "did": "clarence-did",
+            "email": undefined,
+            "emailAuthFactor": false,
+            "emailConfirmed": false,
+            "handle": "clarence.test",
+            "pdsUrl": undefined,
+            "refreshJwt": "clarence-refresh-jwt-2",
+            "service": "https://clarence.com/",
+          },
+        ],
+        "currentAgentState": {
+          "agent": {
+            "service": "https://public.api.bsky.app/",
+          },
+          "did": undefined,
+        },
+        "needsPersist": false,
+      }
+    `)
+  })
+})
+
+function run(initialState: State, actions: Action[]): State {
+  let state = initialState
+  for (let action of actions) {
+    state = reducer(state, action)
+  }
+  return state
+}
+
+function printState(state: State) {
+  return {
+    accounts: state.accounts,
+    currentAgentState: {
+      agent: {service: state.currentAgentState.agent.service},
+      did: state.currentAgentState.did,
+    },
+    needsPersist: state.needsPersist,
+  }
+}
diff --git a/src/state/session/reducer.ts b/src/state/session/reducer.ts
index e873f620..a14cd8e1 100644
--- a/src/state/session/reducer.ts
+++ b/src/state/session/reducer.ts
@@ -6,6 +6,7 @@ import {SessionAccount} from './types'
 // A hack so that the reducer can't read anything from the agent.
 // From the reducer's point of view, it should be a completely opaque object.
 type OpaqueBskyAgent = {
+  readonly service: URL
   readonly api: unknown
   readonly app: unknown
   readonly com: unknown