Give higher priority to .npmignore over .gitignore (#3538)

If .npmignore or .yarnignore are present in a directory that also
contains .gitignore, don't take into account .gitignore when running the
pack command.

New function filterOverridenGitignores takes a WalkFiles object with all
the potential package files and returns another WalkFiles object only
with the relevant dot ignore files (.npmignore, .yarnignore or
.gitignore) taking into account the priority rules. This new collection
is the used by the pack command to create the ignore regexes.

Author: GAumala

__tests__/util/filter.js

@@ -1,6 +1,6 @@
 /* @flow */
 
-import {ignoreLinesToRegex} from '../../src/util/filter.js';
+import {ignoreLinesToRegex, filterOverridenGitignores} from '../../src/util/filter.js';
 
 test('ignoreLinesToRegex', () => {
   expect(
@@ -60,3 +60,26 @@ test('ignoreLinesToRegex', () => {
     {base: '.', isNegation: true, pattern: ' F # # ', regex: /^(?:F # #)$/i},
   ]);
 });
+
+test('filterOverridenGitignores', () => {
+  expect(
+    filterOverridenGitignores([
+      {relative: '.gitignore', basename: '.gitignore', absolute: '/home/user/p/.gitignore', mtime: 0},
+      {relative: '.npmignore', basename: '.npmignore', absolute: '/home/user/p/.npmignore', mtime: 0},
+      {relative: 'docs', basename: 'lib', absolute: '/home/user/p/docs', mtime: 0},
+      {relative: 'docs/file.txt', basename: 'file.txt', absolute: '/home/user/p/docs/file.txt', mtime: 0},
+      {relative: 'index.js', basename: 'index.js', absolute: '/home/user/p/index.js', mtime: 0},
+      {relative: 'lib', basename: 'lib', absolute: '/home/user/p/lib', mtime: 0},
+      {relative: 'lib/.gitignore', basename: '.gitignore', absolute: '/home/user/p/lib/.gitignore', mtime: 0},
+      {relative: 'lib/index.js', basename: 'index.js', absolute: '/home/user/p/lib/index.js', mtime: 0},
+      {relative: 'README.md', basename: 'README.md', absolute: '/home/user/p/README.md', mtime: 0},
+      {relative: 'src', basename: 'src', absolute: '/home/user/p/src', mtime: 0},
+      {relative: 'src/.yarnignore', basename: '.yarnignore', absolute: '/home/user/p/src/.yarnignore', mtime: 0},
+      {relative: 'src/app.js', basename: 'app.js', absolute: '/home/user/p/src/app.js', mtime: 0},
+    ]),
+  ).toEqual([
+    {relative: '.npmignore', basename: '.npmignore', absolute: '/home/user/p/.npmignore', mtime: 0},
+    {relative: 'lib/.gitignore', basename: '.gitignore', absolute: '/home/user/p/lib/.gitignore', mtime: 0},
+    {relative: 'src/.yarnignore', basename: '.yarnignore', absolute: '/home/user/p/src/.yarnignore', mtime: 0},
+  ]);
+});

src/cli/commands/pack.js

@@ -4,7 +4,7 @@ import type {Reporter} from '../../reporters/index.js';
 import type Config from '../../config.js';
 import type {IgnoreFilter} from '../../util/filter.js';
 import * as fs from '../../util/fs.js';
-import {sortFilter, ignoreLinesToRegex} from '../../util/filter.js';
+import {sortFilter, ignoreLinesToRegex, filterOverridenGitignores} from '../../util/filter.js';
 import {MessageError} from '../../errors.js';
 
 const zlib = require('zlib');
@@ -84,18 +84,16 @@ export async function pack(config: Config, dir: string): Promise<stream$Duplex>
     filters = filters.concat(regexes);
   }
 
-  //
   const files = await fs.walk(config.cwd, null, new Set(FOLDERS_IGNORE));
+  const dotIgnoreFiles = filterOverridenGitignores(files);
 
   // create ignores
-  for (const file of files) {
-    if (IGNORE_FILENAMES.indexOf(path.basename(file.relative)) >= 0) {
-      const raw = await fs.readFile(file.absolute);
-      const lines = raw.split('\n');
-
-      const regexes = ignoreLinesToRegex(lines, path.dirname(file.relative));
-      filters = filters.concat(regexes);
-    }
+  for (const file of dotIgnoreFiles) {
+    const raw = await fs.readFile(file.absolute);
+    const lines = raw.split('\n');
+
+    const regexes = ignoreLinesToRegex(lines, path.dirname(file.relative));
+    filters = filters.concat(regexes);
   }
 
   // files to definitely keep, takes precedence over ignore filter

src/util/filter.js

@@ -145,3 +145,22 @@ export function ignoreLinesToRegex(lines: Array<string>, base: string = '.'): Ar
       .filter(Boolean)
   );
 }
+
+export function filterOverridenGitignores(files: WalkFiles): WalkFiles {
+  const IGNORE_FILENAMES = ['.yarnignore', '.npmignore', '.gitignore'];
+  const GITIGNORE_NAME = IGNORE_FILENAMES[2];
+  return files.filter(file => IGNORE_FILENAMES.includes(file.basename)).reduce((acc: WalkFiles, file) => {
+    if (file.basename !== GITIGNORE_NAME) {
+      return [...acc, file];
+    } else {
+      //don't include .gitignore if .npmignore or .yarnignore are present
+      const dir = path.dirname(file.absolute);
+      const higherPriorityIgnoreFilePaths = [`${dir}/${IGNORE_FILENAMES[0]}`, `${dir}/${IGNORE_FILENAMES[1]}`];
+      const hasHigherPriorityFiles = files.find(file => higherPriorityIgnoreFilePaths.includes(file.absolute));
+      if (!hasHigherPriorityFiles) {
+        return [...acc, file];
+      }
+    }
+    return acc;
+  }, []);
+}