Instructions for using Atom text editor.

docs/atom.md

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+# Atom
+
+[TOC]
+
+## Workflow
+
+A typical Atom workflow consists of the following.
+
+1. Use `Ctrl-Shift-R` to find a symbol in the `.tags` file or `Ctrl-P` to find
+   a file by name.
+2. Switch between the header and the source using `Alt-O`.
+3. While editing, `you-complete-me` package helps with C++ auto-completion and
+   shows compile errors through `lint` package.
+4. Press `Ctrl-Shift-P` and type `format<Enter>` to format the code.
+5. Select the target to build by pressing `F7` and typing, for example,
+   `base_unittests`.
+6. Rebuild again by pressing `F9`.
+
+## Atom packages
+
+To setup this workflow, install Atom packages for Chrome development.
+
+```
+$ apm install build-ninja clang-format \
+    linter linter-eslint switch-header-source you-complete-me
+```
+
+## Autocomplete
+
+Install C++ auto-completion engine.
+
+```
+$ git clone https://github.com/Valloric/ycmd.git ~/.ycmd
+$ cd ~/.ycmd
+$ ./build.py --clang-completer
+```
+
+## JavaScript lint
+
+Install JavaScript linter for Blink layout tests.
+
+```
+$ npm install -g eslint eslint-config-google
+```
+
+Configure the JavaScript linter to use the Google style by default by replacing
+the contents of `~/.eslintrc` with the following.
+
+```
+{
+    "extends": "google",
+    "env": {
+      "browser": true
+    }
+}
+```
+
+## Configuration
+
+Configure Atom by replacing the contents of `~/.atom/config.cson` with the
+following. Replace `<path-of-your-home-dir>` and
+`<path-of-your-chrome-checkout>` with the actual full paths of your home
+directory and chrome checkout. For example, these can be `/Users/bob` and
+`/Users/bob/chrome/src`.
+
+```
+"*":
+  # Configure ninja builder.
+  "build-ninja":
+    ninjaOptions: [
+      # The number of jobs to use when running ninja. Adjust to taste.
+      "-j10"
+    ]
+    subdirs: [
+      # The location of your build.ninja file.
+      "out/gn"
+    ]
+  # Do not auto-format entire files on save.
+  "clang-format":
+    formatCOnSave: false
+    formatCPlusPlusOnSave: false
+  core:
+    # Treat .h files as C++.
+    customFileTypes:
+      "source.cpp": [
+        "h"
+      ]
+    # Don't send metrics if you're working on anything sensitive.
+    disabledPackages: [
+      "metrics"
+      "exception-reporting"
+    ]
+  # Use spaces instead of tabs.
+  editor:
+    tabType: "soft"
+  # Show lint errors only when you save the file.
+  linter:
+    lintOnFly: false
+  # Configure JavaScript lint.
+  "linter-eslint":
+    eslintrcPath: "<path-of-your-home-dir>/.eslintrc"
+    useGlobalEslint: true
+  # Don't show ignored files in the project file browser.
+  "tree-view":
+    hideIgnoredNames: true
+    hideVcsIgnoredFiles: true
+  # Configure C++ autocomplete and lint.
+  "you-complete-me":
+    globalExtraConfig: "<path-of-your-chrome-checkout>/tools/vim/chromium.ycm_extra_conf.py"
+    ycmdPath: "<path-of-your-home-dir>/.ycmd/"
+# Java uses 4 space indents and 100 character lines.
+".java.source":
+  editor:
+    preferredLineLength: 100
+    tabLength: 4
+```
+
+## Symbol lookup
+
+Atom fuzzy file finder is slow to index all files in Chrome. If you're working
+on a project that frequently uses `foo` or `bar` in files names, you can create
+a small `.tags` file to efficiently search the symbols within these files. Be
+sure to use "Exuberant Ctags."
+
+```
+$ git ls | egrep -i "foo|bar" | ctags -f .tags -L -
+```
+
+Don't create a ctags file for the full Chrome repository, as that would result
+in ~9GB tag file that will not be usable in Atom.