Files
orca/src/relay/git-handler-branch-diff.test.ts
T
Neil 3713dd7376 perf(git): reuse pinned OIDs for SSH file diffs (#13586)
Forward the renderer's already-pinned {mergeBase, headOid} to the SSH relay so a single-file branch diff reads the two blobs directly instead of rediscovering live HEAD. Six sequential git processes become two concurrent reads, and a branch move mid-review no longer changes which revision is displayed.

Equivalence with the legacy route is proven against real Git across 14 change types; wire compatibility is proven over a real SSH socket against relay bundles built from main and from the pre-merge-base.
2026-08-11 02:18:29 -07:00

393 lines
13 KiB
TypeScript

import { execFileSync } from 'node:child_process'
import { mkdtempSync, rmSync, writeFileSync } from 'node:fs'
import { tmpdir } from 'node:os'
import * as path from 'node:path'
import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest'
import { RelayContext } from './context'
import {
branchDiffEntryAtPinnedOids,
isFullGitObjectId,
parseOptionalBranchDiffHeadOid
} from './git-handler-branch-diff-ops'
import { GitHandler } from './git-handler'
import { branchDiffEntries, type GitBufferExec, type GitExec } from './git-handler-ops'
import {
createMockDispatcher,
gitCommit,
gitInit,
type MockDispatcher,
type RelayDispatcher
} from './git-handler-test-setup'
const BASE_OID = 'a'.repeat(40)
const HEAD_OID = 'b'.repeat(40)
const OTHER_HEAD_OID = 'c'.repeat(40)
const MERGE_BASE_OID = 'd'.repeat(40)
const FILE_PATH = 'src/file.ts'
type GitBufferTarget = {
gitBuffer(args: string[], cwd: string): Promise<Buffer>
}
type GitTarget = {
git(args: string[], cwd: string): Promise<{ stdout: string; stderr: string }>
}
function deferredBuffer(): { promise: Promise<Buffer>; resolve: (content: string) => void } {
let resolve!: (value: Buffer) => void
const promise = new Promise<Buffer>((innerResolve) => {
resolve = innerResolve
})
return { promise, resolve: (content) => resolve(Buffer.from(content)) }
}
describe('pinned relay branch diff operation', () => {
it.each([
{
name: 'addition',
status: `A\t${FILE_PATH}\n`,
left: new Error('missing'),
right: Buffer.from('added\n')
},
{
name: 'deletion',
status: `D\t${FILE_PATH}\n`,
left: Buffer.from('deleted\n'),
right: new Error('missing')
},
{
name: 'binary content',
status: `M\t${FILE_PATH}\n`,
left: Buffer.from([0, 1]),
right: Buffer.from([0, 2])
},
{
name: 'blob read failure',
status: `M\t${FILE_PATH}\n`,
left: new Error('left failed'),
right: new Error('right failed')
}
])('matches the legacy $name result', async ({ status, left, right }) => {
const createGitBuffer = (): GitBufferExec =>
vi.fn<GitBufferExec>(async (args) => {
const value = args[2].startsWith(`${BASE_OID}:`) ? left : right
if (value instanceof Error) {
throw value
}
return value
})
const git = vi.fn<GitExec>(async (args) => {
if (args[0] === 'rev-parse' && args.includes('HEAD')) {
return { stdout: `${HEAD_OID}\n`, stderr: '' }
}
if (args[0] === 'rev-parse' || args[0] === 'merge-base') {
return { stdout: `${BASE_OID}\n`, stderr: '' }
}
return { stdout: status, stderr: '' }
})
const pinned = await branchDiffEntryAtPinnedOids(
createGitBuffer(),
'/repo',
BASE_OID,
HEAD_OID,
FILE_PATH
)
const legacy = await branchDiffEntries(git, createGitBuffer(), '/repo', BASE_OID, {
includePatch: true,
filePath: FILE_PATH
})
expect(pinned).toEqual(legacy)
})
// Why: GitBranchCompareSummary.headOid is `string | null`, so an unpinned
// snapshot arrives as an explicit null and must stay servable.
it.each([
{ name: 'absent', params: {} },
{ name: 'null', params: { headOid: null } },
{ name: 'undefined', params: { headOid: undefined } }
])('treats a $name head OID as unpinned', ({ params }) => {
expect(parseOptionalBranchDiffHeadOid(params)).toBeUndefined()
})
it.each([
{ name: 'SHA-1', headOid: HEAD_OID },
{ name: 'SHA-256', headOid: 'b'.repeat(64) }
])('returns a supplied $name head OID', ({ headOid }) => {
expect(parseOptionalBranchDiffHeadOid({ headOid })).toBe(headOid)
})
it.each([{ headOid: 'abc123' }, { headOid: '' }, { headOid: 'main' }, { headOid: 123 }])(
'rejects the supplied malformed head OID $headOid',
({ headOid }) => {
expect(() => parseOptionalBranchDiffHeadOid({ headOid })).toThrow(
'headOid must be a full git object id'
)
}
)
it('recognizes only full object ids', () => {
expect(isFullGitObjectId(BASE_OID)).toBe(true)
expect(isFullGitObjectId('A'.repeat(64))).toBe(true)
for (const value of ['origin/main', 'abc123', '', 'g'.repeat(40), null, undefined, 123, {}]) {
expect(isFullGitObjectId(value)).toBe(false)
}
})
// Why: the route guards this today, but the export is reachable on its own —
// a symbolic ref here would resolve `git show origin/main:<path>` at live HEAD.
it('rejects a symbolic ref at the module boundary', async () => {
const gitBuffer = vi.fn<GitBufferExec>(async () => Buffer.from(''))
await expect(
branchDiffEntryAtPinnedOids(gitBuffer, '/repo', 'origin/main', HEAD_OID, FILE_PATH)
).rejects.toThrow('baseRef must be a full git object id')
await expect(
branchDiffEntryAtPinnedOids(gitBuffer, '/repo', BASE_OID, 'HEAD', FILE_PATH)
).rejects.toThrow('headOid must be a full git object id')
expect(gitBuffer).not.toHaveBeenCalled()
})
})
describe('GitHandler pinned branch diff route', () => {
let dispatcher: MockDispatcher
let handler: GitHandler
beforeEach(() => {
dispatcher = createMockDispatcher()
handler = new GitHandler(dispatcher as unknown as RelayDispatcher, new RelayContext())
})
afterEach(() => {
handler.dispose()
vi.restoreAllMocks()
})
function request(overrides: Record<string, unknown> = {}): Promise<unknown> {
return dispatcher.callRequest('git.branchDiff', {
worktreePath: '/repo',
baseRef: BASE_OID,
headOid: HEAD_OID,
includePatch: true,
filePath: FILE_PATH,
...overrides
})
}
function mockLegacyGit(nameStatus = '') {
return vi.spyOn(handler as unknown as GitTarget, 'git').mockImplementation(async (args) => {
if (args[0] === 'rev-parse' && args.includes('HEAD')) {
return { stdout: `${HEAD_OID}\n`, stderr: '' }
}
if (args[0] === 'rev-parse') {
return { stdout: `${BASE_OID}\n`, stderr: '' }
}
if (args[0] === 'merge-base') {
return { stdout: `${MERGE_BASE_OID}\n`, stderr: '' }
}
return { stdout: nameStatus, stderr: '' }
})
}
it('starts exactly two pinned blob reads concurrently without metadata commands', async () => {
const left = deferredBuffer()
const right = deferredBuffer()
const gitBufferSpy = vi
.spyOn(handler as unknown as GitBufferTarget, 'gitBuffer')
.mockImplementation((args) => {
if (args[2] === `${BASE_OID}:${FILE_PATH}`) {
return left.promise
}
if (args[2] === `${HEAD_OID}:${FILE_PATH}`) {
return right.promise
}
throw new Error(`unexpected blob spec: ${args[2]}`)
})
const gitSpy = vi
.spyOn(handler as unknown as GitTarget, 'git')
.mockRejectedValue(new Error('metadata command should not run'))
const resultPromise = request()
await vi.waitFor(() => expect(gitBufferSpy).toHaveBeenCalledTimes(2))
expect(gitSpy).not.toHaveBeenCalled()
expect(gitBufferSpy.mock.calls.map(([args]) => args)).toEqual([
['show', '--end-of-options', `${BASE_OID}:${FILE_PATH}`],
['show', '--end-of-options', `${HEAD_OID}:${FILE_PATH}`]
])
left.resolve('before\n')
right.resolve('after\n')
await expect(resultPromise).resolves.toEqual([
{
kind: 'text',
originalContent: 'before\n',
modifiedContent: 'after\n',
originalIsBinary: false,
modifiedIsBinary: false
}
])
})
it('reads the old path only from the base OID', async () => {
const oldPath = 'src/old-file.ts'
const gitBufferSpy = vi
.spyOn(handler as unknown as GitBufferTarget, 'gitBuffer')
.mockImplementation(async (args) => Buffer.from(args[2].startsWith(BASE_OID) ? 'old' : 'new'))
await request({ oldPath })
expect(gitBufferSpy.mock.calls.map(([args]) => args[2])).toEqual([
`${BASE_OID}:${oldPath}`,
`${HEAD_OID}:${FILE_PATH}`
])
})
it('coalesces the same head OID while keeping different heads independent', async () => {
const pending = deferredBuffer()
const gitBufferSpy = vi
.spyOn(handler as unknown as GitBufferTarget, 'gitBuffer')
.mockImplementation(() => pending.promise)
const requests = [request(), request(), request({ headOid: OTHER_HEAD_OID })]
await vi.waitFor(() => expect(gitBufferSpy).toHaveBeenCalledTimes(4))
const specs = gitBufferSpy.mock.calls.map(([args]) => args[2])
expect(specs.filter((spec) => spec === `${BASE_OID}:${FILE_PATH}`)).toHaveLength(2)
expect(specs.filter((spec) => spec === `${HEAD_OID}:${FILE_PATH}`)).toHaveLength(1)
expect(specs.filter((spec) => spec === `${OTHER_HEAD_OID}:${FILE_PATH}`)).toHaveLength(1)
pending.resolve('content\n')
await Promise.all(requests)
})
it('rejects every supplied malformed head OID before running Git', async () => {
const gitBufferSpy = vi.spyOn(handler as unknown as GitBufferTarget, 'gitBuffer')
const invalidHeadOids = [7, {}, '', 'a'.repeat(39), 'g'.repeat(40)]
for (const headOid of invalidHeadOids) {
await expect(request({ headOid })).rejects.toThrow('headOid must be a full git object id')
}
expect(gitBufferSpy).not.toHaveBeenCalled()
})
it('accepts SHA-256 object IDs', async () => {
const baseOid = 'A'.repeat(64)
const headOid = 'b'.repeat(64)
const gitBufferSpy = vi
.spyOn(handler as unknown as GitBufferTarget, 'gitBuffer')
.mockResolvedValue(Buffer.from('content\n'))
await request({ baseRef: baseOid, headOid })
expect(gitBufferSpy.mock.calls.map(([args]) => args[2])).toEqual([
`${baseOid}:${FILE_PATH}`,
`${headOid}:${FILE_PATH}`
])
})
// Why: a symbolic base ref used to select the pinned route and then throw.
it('selects the pinned route only when the base ref is a full object id', async () => {
const gitSpy = mockLegacyGit(`M\t${FILE_PATH}\n`)
const gitBufferSpy = vi
.spyOn(handler as unknown as GitBufferTarget, 'gitBuffer')
.mockResolvedValue(Buffer.from('content\n'))
await expect(request({ baseRef: 'origin/main' })).resolves.toHaveLength(1)
expect(gitSpy.mock.calls.map(([args]) => args.join(' '))).toEqual([
'rev-parse --verify HEAD',
'rev-parse --verify origin/main',
`merge-base ${BASE_OID} ${HEAD_OID}`,
`-c core.quotePath=false diff --name-status -M -C ${MERGE_BASE_OID} ${HEAD_OID}`
])
expect(gitBufferSpy.mock.calls.map(([args]) => args[2])).toEqual([
`${MERGE_BASE_OID}:${FILE_PATH}`,
`${HEAD_OID}:${FILE_PATH}`
])
gitSpy.mockClear()
gitBufferSpy.mockClear()
await request()
expect(gitSpy).not.toHaveBeenCalled()
expect(gitBufferSpy.mock.calls.map(([args]) => args[2])).toEqual([
`${BASE_OID}:${FILE_PATH}`,
`${HEAD_OID}:${FILE_PATH}`
])
})
it('serves an explicitly null head OID through the legacy path', async () => {
const gitSpy = mockLegacyGit(`M\t${FILE_PATH}\n`)
const gitBufferSpy = vi.spyOn(handler as unknown as GitBufferTarget, 'gitBuffer')
await expect(request({ headOid: null, includePatch: false })).resolves.toEqual([
{
kind: 'text',
originalContent: '',
modifiedContent: '',
originalIsBinary: false,
modifiedIsBinary: false
}
])
expect(gitSpy).toHaveBeenCalledTimes(4)
expect(gitBufferSpy).not.toHaveBeenCalled()
})
it('uses the legacy path when patch or file-path conditions are not met', async () => {
const gitSpy = mockLegacyGit()
const gitBufferSpy = vi.spyOn(handler as unknown as GitBufferTarget, 'gitBuffer')
await Promise.all([
request({ baseRef: 'main', includePatch: false }),
request({ baseRef: 'main', filePath: '' }),
request({ baseRef: 'main', filePath: { malformed: true } })
])
expect(gitSpy).toHaveBeenCalledTimes(12)
expect(gitBufferSpy).not.toHaveBeenCalled()
})
it('keeps the requested head pinned after repository HEAD moves', async () => {
const repoPath = mkdtempSync(path.join(tmpdir(), 'relay-pinned-branch-diff-'))
try {
gitInit(repoPath)
writeFileSync(path.join(repoPath, 'file.txt'), 'base\n')
gitCommit(repoPath, 'base')
const baseOid = execFileSync('git', ['rev-parse', 'HEAD'], {
cwd: repoPath,
encoding: 'utf8'
}).trim()
writeFileSync(path.join(repoPath, 'file.txt'), 'pinned\n')
gitCommit(repoPath, 'pinned')
const pinnedHeadOid = execFileSync('git', ['rev-parse', 'HEAD'], {
cwd: repoPath,
encoding: 'utf8'
}).trim()
writeFileSync(path.join(repoPath, 'file.txt'), 'moved\n')
gitCommit(repoPath, 'moved')
const result = (await request({
worktreePath: repoPath,
baseRef: baseOid,
headOid: pinnedHeadOid,
filePath: 'file.txt'
})) as { originalContent: string; modifiedContent: string }[]
expect(result[0]).toMatchObject({
originalContent: 'base\n',
modifiedContent: 'pinned\n'
})
expect(
execFileSync('git', ['show', 'HEAD:file.txt'], { cwd: repoPath, encoding: 'utf8' })
).toBe('moved\n')
} finally {
rmSync(repoPath, { recursive: true, force: true })
}
})
})