feat(codex): auto-install git bash via winget on windows

src/cli/install-codex/git-bash.test.ts

@@ -2,7 +2,7 @@
 /// <reference types="bun-types" />
 
 import { describe, expect, test } from "bun:test"
-import { resolveGitBash } from "./git-bash"
+import { prepareGitBashForInstall, resolveGitBash } from "./git-bash"
 
 const PROGRAM_FILES_GIT_BASH = "C:\\Program Files\\Git\\bin\\bash.exe"
 const PROGRAM_FILES_X86_GIT_BASH = "C:\\Program Files (x86)\\Git\\bin\\bash.exe"
@@ -115,4 +115,74 @@ describe("git-bash", () => {
     expect(result.installHint).toContain("OMO_CODEX_GIT_BASH_PATH=C:\\path\\to\\bash.exe")
     expect(result.installHint).toContain("rerun `bunx omo install --platform=codex`")
   })
+
+  test("#given Windows without Git Bash and winget is allowed #when preparing #then winget runs and resolver is retried", async () => {
+    // given
+    const runCalls: string[] = []
+    const resolutions = [
+      { found: false, checkedPaths: [PROGRAM_FILES_GIT_BASH], installHint: "install hint" } as const,
+      { found: true, path: PROGRAM_FILES_GIT_BASH, source: "program-files" } as const,
+    ]
+    let resolveCallCount = 0
+
+    // when
+    const result = await prepareGitBashForInstall({
+      platform: "win32",
+      env: {},
+      cwd: "C:\\repo",
+      resolveGitBash: () => resolutions[resolveCallCount++] ?? resolutions[resolutions.length - 1],
+      runCommand: async (command, args, options) => {
+        runCalls.push([command, ...args, options.cwd].join(" "))
+      },
+    })
+
+    // then
+    expect(runCalls).toEqual(["winget install --id Git.Git -e --source winget C:\\repo"])
+    expect(resolveCallCount).toBe(2)
+    expect(result).toEqual({ found: true, path: PROGRAM_FILES_GIT_BASH, source: "program-files" })
+  })
+
+  test("#given Windows without Git Bash and skip env is set #when preparing #then winget is not run and install hint is returned", async () => {
+    // given
+    const runCalls: string[] = []
+    const missingResolution = {
+      found: false,
+      checkedPaths: [PROGRAM_FILES_GIT_BASH, PROGRAM_FILES_X86_GIT_BASH],
+      installHint: "install hint",
+    } as const
+
+    // when
+    const result = await prepareGitBashForInstall({
+      platform: "win32",
+      env: { OMO_CODEX_SKIP_GIT_BASH_AUTO_INSTALL: "1" },
+      cwd: "C:\\repo",
+      resolveGitBash: () => missingResolution,
+      runCommand: async (command, args, options) => {
+        runCalls.push([command, ...args, options.cwd].join(" "))
+      },
+    })
+
+    // then
+    expect(runCalls).toEqual([])
+    expect(result).toEqual(missingResolution)
+  })
+
+  test("#given non-Windows platform #when preparing #then winget is never called", async () => {
+    // given
+    const runCalls: string[] = []
+
+    // when
+    const result = await prepareGitBashForInstall({
+      platform: "linux",
+      env: {},
+      cwd: "/repo",
+      runCommand: async (command, args, options) => {
+        runCalls.push([command, ...args, options.cwd].join(" "))
+      },
+    })
+
+    // then
+    expect(runCalls).toEqual([])
+    expect(result).toEqual({ found: true, path: null, source: "not-required" })
+  })
 })