fix: handle absolute paths correctly

Fixes #1.

package.json

@@ -32,8 +32,9 @@
     "mock-bin": "^1.0.1",
     "mock-git": "^1.0.3",
     "mz": "^2.6.0",
-    "tmp-promise": "^1.0.3",
-    "semantic-release": "^6.3.6"
+    "pmock": "^0.2.3",
+    "semantic-release": "^6.3.6",
+    "tmp-promise": "^1.0.3"
   },
   "engines": {
     "node": ">=6",

src/__mocks__/TestEnvironment.js

@@ -3,6 +3,7 @@ import mockBin from "mock-bin";
 import tmp from "tmp-promise";
 import path from "path";
 import fs from "mz/fs";
+import pmock from "pmock";
 
 export default class TestEnvironment {
   _unmock = [];
@@ -53,6 +54,8 @@ export default class TestEnvironment {
   async setup() {
     this._spyLogFile = await tmp.tmpName();
     this._unmock.push(await mockGit(this._makeSpyJs("git"), "add"));
+    const cwdMock = pmock.cwd("/path/to/repo");
+    this._unmock.push(() => cwdMock.reset());
     await this.setAllStagedFiles();
     await this.setPartialFiles();
   }

src/__tests__/__snapshots__/index.test.js.snap

@@ -10,6 +10,14 @@ Array [
 ]
 `;
 
+exports[`git-exec-and-restage with command+args and mixed status, absolute paths 1`] = `
+Array [
+  "git diff --name-only --diff-filter=ACDMRTUXB fullystaged.js partiallystaged.js",
+  "prettier --write /path/to/repo/fullystaged.js /path/to/repo/partiallystaged.js",
+  "git add fullystaged.js",
+]
+`;
+
 exports[`git-exec-and-restage with command+args, files implicit 1`] = `
 Array [
   "git diff-index --cached --name-only --diff-filter=ACDMRTUXB HEAD",

src/__tests__/index.test.js

@@ -1,5 +1,6 @@
 import gitExecAndRestage from "../";
 import TestEnvironment from "TestEnvironment";
+import path from "path";
 
 describe("git-exec-and-restage", () => {
   const env = new TestEnvironment();
@@ -20,11 +21,13 @@ describe("git-exec-and-restage", () => {
   });
   it("with command, arguments, fully staged file, no partials", async () => {
     await env.mockBin("prettier");
+    await env.setAllStagedFiles(["fullystaged.js"]);
     await gitExecAndRestage(["prettier", "--write", "--", "fullystaged.js"]);
     expect(await env.log).toMatchSnapshot();
   });
   it("with command+args, mix of fully and partially staged files", async () => {
     await env.mockBin("prettier");
+    await env.setAllStagedFiles(["fullystaged.js", "partiallystaged.js"]);
     await env.setPartialFiles(["partiallystaged.js"]);
     await gitExecAndRestage([
       "prettier",
@@ -54,4 +57,17 @@ describe("git-exec-and-restage", () => {
     await gitExecAndRestage(["prettier", "--write", "--", "fullystaged1.js"]);
     expect(await env.log).toMatchSnapshot();
   });
+  it("with command+args and mixed status, absolute paths", async () => {
+    await env.mockBin("prettier");
+    await env.setAllStagedFiles(["fullystaged.js", "partiallystaged.js"]);
+    await env.setPartialFiles(["partiallystaged.js"]);
+    await gitExecAndRestage([
+      "prettier",
+      "--write",
+      "--",
+      path.join(process.cwd(), "fullystaged.js"),
+      path.join(process.cwd(), "partiallystaged.js")
+    ]);
+    expect(await env.log).toMatchSnapshot();
+  });
 });

src/gitUtils.js

@@ -1,4 +1,12 @@
 import spawn from "cross-spawn-promise";
+import path from "path";
+
+function ensureRelativePath(s) {
+  if (path.isAbsolute(s)) {
+    return path.relative(process.cwd(), s);
+  }
+  return s;
+}
 
 async function getAllStaged() {
   const diffOut =
@@ -28,13 +36,36 @@ async function getFullyStaged(
   const diffOut =
     (await spawn(
       "git",
-      ["diff", "--name-only", "--diff-filter=ACDMRTUXB", ...files],
+      [
+        "diff",
+        "--name-only",
+        "--diff-filter=ACDMRTUXB",
+        ...files.map(filename => ensureRelativePath(filename))
+      ],
       {
         encoding: "utf8"
       }
     )) || "";
-  const notFullyStaged = new Set(diffOut.split("\n").filter(s => s !== ""));
-  return files.filter(file => !notFullyStaged.has(file));
+  const notFullyStaged = new Set(
+    diffOut
+      .split("\n")
+      .filter(s => s !== "")
+      .map(filename => path.resolve(process.cwd(), filename))
+  );
+  return files.filter(
+    file => !notFullyStaged.has(path.resolve(process.cwd(), file))
+  );
+}
+
+async function stageFiles(
+  /* istanbul ignore next: convenience default */
+  files = []
+) {
+  await spawn(
+    "git",
+    ["add", ...files.map(filename => ensureRelativePath(filename))],
+    { stdio: "inherit" }
+  );
 }
 
-export { getAllStaged, getFullyStaged };
+export { getAllStaged, getFullyStaged, stageFiles };

src/index.js

@@ -2,7 +2,7 @@
 
 import spawn from "cross-spawn-promise";
 import CliError from "./CliError";
-import { getAllStaged, getFullyStaged } from "./gitUtils";
+import { getAllStaged, getFullyStaged, stageFiles } from "./gitUtils";
 
 export { CliError };
 
@@ -18,7 +18,7 @@ async function main(argv = []) {
   const fullyStaged = await getFullyStaged(files);
   await spawn(command, commandArgs.concat(files), { stdio: "inherit" });
   if (fullyStaged.length) {
-    await spawn("git", ["add", ...fullyStaged], { stdio: "inherit" });
+    await stageFiles(fullyStaged);
   }
 }