From 9828730ad8c6c4861fd337023d3a07e158a5d84a Mon Sep 17 00:00:00 2001
From: Lucas Azzola <derflatulator@gmail.com>
Date: Wed, 20 Sep 2017 22:14:10 +1000
Subject: [PATCH 1/8] [jest-docblock]: add docblock.print()

---
 packages/jest-docblock/README.md              |  8 +-
 .../jest-docblock/src/__tests__/index.test.js | 76 +++++++++++++++++++
 packages/jest-docblock/src/index.js           | 48 ++++++++++++
 3 files changed, 131 insertions(+), 1 deletion(-)

diff --git a/packages/jest-docblock/README.md b/packages/jest-docblock/README.md
index 41f021a912c2..26d7009d992d 100644
--- a/packages/jest-docblock/README.md
+++ b/packages/jest-docblock/README.md
@@ -30,6 +30,7 @@ Pragmas can also take arguments:
 `jest-docblock` can:
 * extract the docblock from some code as a string
 * parse a docblock string's pragmas into an object
+* print an object and some comments back to a string
 
 ## Installation
 ```sh
@@ -56,13 +57,15 @@ const code = `
  }
 `;
 
-const { extract, parse } = require("jest-docblock");
+const { extract, parse, print } = require("jest-docblock");
 
 const docblock = extract(code);
 console.log(docblock); // "/**\n * Everything is awesome!\n * \n * @everything is:awesome\n * @flow\n */"
 
 const pragmas = parse(docblock);
 console.log(pragmas); // { everything: "is:awesome", flow: "" }
+
+console.log(print(pragmas), "hi!") // /**\n * hi!\n *\n * @everything is:awesome\n * @flow */;
 ```
 
 ## API Documentation
@@ -72,3 +75,6 @@ Extracts a docblock from some file contents. Returns the docblock contained in `
 
 ### `parse(docblock: string): {[key: string]: string}`
 Parses the pragmas in a docblock string into an object whose keys are the pragma tags and whose values are the arguments to those pragmas.
+
+### `print(object: {[key: string]: string}, comments?: string): string`
+Prints an object of key-value pairs back into a docblock. If `comments` are provided, they will be positioned on the top of the docblock.
\ No newline at end of file
diff --git a/packages/jest-docblock/src/__tests__/index.test.js b/packages/jest-docblock/src/__tests__/index.test.js
index ba58b1aed701..73e51ddc3cbc 100644
--- a/packages/jest-docblock/src/__tests__/index.test.js
+++ b/packages/jest-docblock/src/__tests__/index.test.js
@@ -213,4 +213,80 @@ describe('docblock', () => {
       providesModule: 'apple/banana',
     });
   });
+
+  it('prints docblocks with no keys as empty string', () => {
+    const object = {};
+    expect(docblock.print(object)).toEqual('');
+  });
+
+  it('prints docblocks with one key on one line', () => {
+    const object = {flow: ''};
+    expect(docblock.print(object)).toEqual('/** @flow */');
+  });
+
+  it('prints docblocks with multiple keys on multiple lines', () => {
+    const object = {
+      flow: '',
+      format: '',
+    };
+    expect(docblock.print(object)).toEqual(
+      '/**' + os.EOL + ' * @flow' + os.EOL + ' * @format' + os.EOL + ' */',
+    );
+  });
+
+  it('prints docblocks with values', () => {
+    const object = {
+      flow: 'foo',
+      providesModule: 'x/y/z',
+    };
+    expect(docblock.print(object)).toEqual(
+      '/**' +
+        os.EOL +
+        ' * @flow foo' +
+        os.EOL +
+        ' * @providesModule x/y/z' +
+        os.EOL +
+        ' */',
+    );
+  });
+
+  it('prints docblocks with comments', () => {
+    const object = {flow: 'foo'};
+    const comments = 'hello';
+    expect(docblock.print(object, comments)).toEqual(
+      '/**' +
+        os.EOL +
+        ' * hello' +
+        os.EOL +
+        ' *' +
+        os.EOL +
+        ' * @flow foo' +
+        os.EOL +
+        ' */',
+    );
+  });
+
+  it('prints docblocks with comments and no keys', () => {
+    const object = {};
+    const comments = 'Copyright 2004-present Facebook. All Rights Reserved.';
+    expect(docblock.print(object, comments)).toEqual(
+      '/**' + os.EOL + ' * ' + comments + os.EOL + ' */',
+    );
+  });
+
+  it('prints docblocks with multiline comments', () => {
+    const object = {};
+    const comments = 'hello' + os.EOL + 'world';
+    expect(docblock.print(object, comments)).toEqual(
+      '/**' + os.EOL + ' * hello' + os.EOL + ' * world' + os.EOL + ' */',
+    );
+  });
+
+  it('prints docblocks that are parseable', () => {
+    const object = {a: 'b', c: ''};
+    const comments = 'hello world!';
+    const formatted = docblock.print(object, comments);
+    const parsed = docblock.parse(formatted);
+    expect(parsed).toEqual(object);
+  });
 });
diff --git a/packages/jest-docblock/src/index.js b/packages/jest-docblock/src/index.js
index 18e0a8d49f6b..0f4cbefd015c 100644
--- a/packages/jest-docblock/src/index.js
+++ b/packages/jest-docblock/src/index.js
@@ -8,6 +8,8 @@
  * @flow
  */
 
+const os = require('os');
+
 const commentEndRe = /\*\/$/;
 const commentStartRe = /^\/\*\*/;
 const docblockRe = /^\s*(\/\*\*?(.|\r?\n)*?\*\/)/;
@@ -47,5 +49,51 @@ function parse(docblock: string): {[key: string]: string} {
   return result;
 }
 
+function print(object: {[key: string]: string} = {}, comments = ''): string {
+  const head = '/**';
+  const start = ' *';
+  const tail = ' */';
+
+  const keys = Object.keys(object);
+  const line = os.EOL;
+
+  const printedObject = keys
+    .reduce(
+      (acc, key) =>
+        acc.concat(start, ' ', printKeyValue(key, object[key]), line),
+      [],
+    )
+    .join('');
+
+  if (!comments) {
+    if (keys.length === 0) {
+      return '';
+    }
+    if (keys.length === 1) {
+      return `${head} ${printKeyValue(keys[0], object[keys[0]])}${tail}`;
+    }
+  }
+
+  const printedComments =
+    comments
+      .split(os.EOL)
+      .map(textLine => `${start} ${textLine}`)
+      .join(os.EOL) + os.EOL;
+
+  return (
+    head +
+    line +
+    (comments ? printedComments : '') +
+    (comments && keys.length ? start + line : '') +
+    printedObject +
+    tail
+  );
+}
+
+function printKeyValue(key, value) {
+  return `@${key} ${value}`.trim();
+}
+
 exports.extract = extract;
 exports.parse = parse;
+exports.print = print;

From 17d8f0fc5b89ece92bfaa8fe2ccb9849dfa934e2 Mon Sep 17 00:00:00 2001
From: Lucas Azzola <derflatulator@gmail.com>
Date: Wed, 20 Sep 2017 22:41:58 +1000
Subject: [PATCH 2/8] Add missing flow type, clean up

---
 packages/jest-docblock/src/index.js | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/packages/jest-docblock/src/index.js b/packages/jest-docblock/src/index.js
index 0f4cbefd015c..22635fbb9fe2 100644
--- a/packages/jest-docblock/src/index.js
+++ b/packages/jest-docblock/src/index.js
@@ -49,7 +49,10 @@ function parse(docblock: string): {[key: string]: string} {
   return result;
 }
 
-function print(object: {[key: string]: string} = {}, comments = ''): string {
+function print(
+  object: {[key: string]: string} = {},
+  comments: string = '',
+): string {
   const head = '/**';
   const start = ' *';
   const tail = ' */';
@@ -58,11 +61,7 @@ function print(object: {[key: string]: string} = {}, comments = ''): string {
   const line = os.EOL;
 
   const printedObject = keys
-    .reduce(
-      (acc, key) =>
-        acc.concat(start, ' ', printKeyValue(key, object[key]), line),
-      [],
-    )
+    .map(key => start + ' ' + printKeyValue(key, object[key]) + line)
     .join('');
 
   if (!comments) {

From 130628f6cc98c71870767566951548e50220b083 Mon Sep 17 00:00:00 2001
From: Lucas Azzola <derflatulator@gmail.com>
Date: Wed, 20 Sep 2017 22:43:42 +1000
Subject: [PATCH 3/8] Fix docs typo

---
 packages/jest-docblock/README.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/jest-docblock/README.md b/packages/jest-docblock/README.md
index 26d7009d992d..7dfca75585a5 100644
--- a/packages/jest-docblock/README.md
+++ b/packages/jest-docblock/README.md
@@ -65,7 +65,7 @@ console.log(docblock); // "/**\n * Everything is awesome!\n * \n * @everything i
 const pragmas = parse(docblock);
 console.log(pragmas); // { everything: "is:awesome", flow: "" }
 
-console.log(print(pragmas), "hi!") // /**\n * hi!\n *\n * @everything is:awesome\n * @flow */;
+console.log(print(pragmas), "hi!") // /**\n * hi!\n *\n * @everything is:awesome\n * @flow\n */;
 ```
 
 ## API Documentation

From 66fdd4a78c80ab9e8e6eb4cdd8c9c54021eb69a5 Mon Sep 17 00:00:00 2001
From: Lucas Azzola <derflatulator@gmail.com>
Date: Wed, 20 Sep 2017 23:31:31 +1000
Subject: [PATCH 4/8] Fix doc typo

---
 packages/jest-docblock/README.md | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/packages/jest-docblock/README.md b/packages/jest-docblock/README.md
index 7dfca75585a5..35f3b9d0b5a3 100644
--- a/packages/jest-docblock/README.md
+++ b/packages/jest-docblock/README.md
@@ -65,7 +65,7 @@ console.log(docblock); // "/**\n * Everything is awesome!\n * \n * @everything i
 const pragmas = parse(docblock);
 console.log(pragmas); // { everything: "is:awesome", flow: "" }
 
-console.log(print(pragmas), "hi!") // /**\n * hi!\n *\n * @everything is:awesome\n * @flow\n */;
+console.log(print(pragmas, "hi!")) // /**\n * hi!\n *\n * @everything is:awesome\n * @flow\n */;
 ```
 
 ## API Documentation
@@ -77,4 +77,4 @@ Extracts a docblock from some file contents. Returns the docblock contained in `
 Parses the pragmas in a docblock string into an object whose keys are the pragma tags and whose values are the arguments to those pragmas.
 
 ### `print(object: {[key: string]: string}, comments?: string): string`
-Prints an object of key-value pairs back into a docblock. If `comments` are provided, they will be positioned on the top of the docblock.
\ No newline at end of file
+Prints an object of key-value pairs back into a docblock. If `comments` are provided, they will be positioned on the top of the docblock.

From c0b6a97edb5b5446a0a8602d8c9cb41b18a7785b Mon Sep 17 00:00:00 2001
From: Lucas Azzola <derflatulator@gmail.com>
Date: Thu, 21 Sep 2017 11:10:56 +1000
Subject: [PATCH 5/8] [WIP] add docblock.parseWithComments()

---
 packages/jest-docblock/README.md              |  5 +-
 .../jest-docblock/src/__tests__/index.test.js | 51 +++++++++++++++++++
 packages/jest-docblock/src/index.js           | 20 +++++---
 3 files changed, 67 insertions(+), 9 deletions(-)

diff --git a/packages/jest-docblock/README.md b/packages/jest-docblock/README.md
index 35f3b9d0b5a3..4d72b4fc2eaf 100644
--- a/packages/jest-docblock/README.md
+++ b/packages/jest-docblock/README.md
@@ -76,5 +76,8 @@ Extracts a docblock from some file contents. Returns the docblock contained in `
 ### `parse(docblock: string): {[key: string]: string}`
 Parses the pragmas in a docblock string into an object whose keys are the pragma tags and whose values are the arguments to those pragmas.
 
+### `parseWithComments(docblock: string): { comments: string, pragmas: {[key: string]: string} }`
+Similar to `parse` except this method also returns the comments from the docblock. Useful when used with `print()`.
+
 ### `print(object: {[key: string]: string}, comments?: string): string`
-Prints an object of key-value pairs back into a docblock. If `comments` are provided, they will be positioned on the top of the docblock.
+Prints an object of key-value pairs back into a docblock. If `comments` are provided, they will be positioned on the top of the docblock.
\ No newline at end of file
diff --git a/packages/jest-docblock/src/__tests__/index.test.js b/packages/jest-docblock/src/__tests__/index.test.js
index 73e51ddc3cbc..e0466759429a 100644
--- a/packages/jest-docblock/src/__tests__/index.test.js
+++ b/packages/jest-docblock/src/__tests__/index.test.js
@@ -214,6 +214,57 @@ describe('docblock', () => {
     });
   });
 
+  it('extracts comments from docblock', () => {
+    const code =
+      '/**' +
+      os.EOL +
+      ' * hello world' +
+      os.EOL +
+      ' * @flow yes' +
+      os.EOL +
+      ' */';
+    expect(docblock.parseWithComments(code)).toEqual({
+      comments: 'hello world',
+      pragmas: {flow: 'yes'},
+    });
+  });
+
+  it('extracts multiline comments from docblock', () => {
+    const code =
+      '/**' +
+      os.EOL +
+      ' * hello' +
+      os.EOL +
+      ' * world' +
+      os.EOL +
+      ' * @flow yes' +
+      os.EOL +
+      ' */';
+    expect(docblock.parseWithComments(code)).toEqual({
+      comments: 'hello\nworld',
+      pragmas: {flow: 'yes'},
+    });
+  });
+
+  it('extracts comments from beginning and end of docblock', () => {
+    const code =
+      '/**' +
+      os.EOL +
+      ' * hello' +
+      os.EOL +
+      ' * @flow yes' +
+      os.EOL +
+      ' * ' +
+      os.EOL +
+      ' * world' +
+      os.EOL +
+      ' */';
+    expect(docblock.parseWithComments(code)).toEqual({
+      comments: 'hello\n\nworld',
+      pragmas: {flow: 'yes'},
+    });
+  });
+
   it('prints docblocks with no keys as empty string', () => {
     const object = {};
     expect(docblock.print(object)).toEqual('');
diff --git a/packages/jest-docblock/src/index.js b/packages/jest-docblock/src/index.js
index 22635fbb9fe2..91f8e9dba63e 100644
--- a/packages/jest-docblock/src/index.js
+++ b/packages/jest-docblock/src/index.js
@@ -18,14 +18,21 @@ const ltrimRe = /^\s*/;
 const multilineRe = /(?:^|\r?\n) *(@[^\r\n]*?) *\r?\n *([^@\r\n\s][^@\r\n]+?) *\r?\n/g;
 const propertyRe = /(?:^|\r?\n) *@(\S+) *([^\r\n]*)/g;
 const stringStartRe = /(\r?\n|^) *\*/g;
+const lineStartRe = /(?:\r?\n|^) */g;
 const wsRe = /[\t ]+/g;
 
-function extract(contents: string): string {
+export function extract(contents: string): string {
   const match = contents.match(docblockRe);
   return match ? match[0].replace(ltrimRe, '') || '' : '';
 }
 
-function parse(docblock: string): {[key: string]: string} {
+export function parse(docblock: string): {[key: string]: string} {
+  return parseWithComments(docblock).pragmas;
+}
+
+export function parseWithComments(
+  docblock: string,
+): {comments: string, pragmas: {[key: string]: string}} {
   docblock = docblock
     .replace(commentStartRe, '')
     .replace(commentEndRe, '')
@@ -42,14 +49,15 @@ function parse(docblock: string): {[key: string]: string} {
   docblock = docblock.trim();
 
   const result = Object.create(null);
+  const comments = docblock.replace(propertyRe, '').replace(lineStartRe, '\n');
   let match;
   while ((match = propertyRe.exec(docblock))) {
     result[match[1]] = match[2];
   }
-  return result;
+  return {comments: comments.trim(), pragmas: result};
 }
 
-function print(
+export function print(
   object: {[key: string]: string} = {},
   comments: string = '',
 ): string {
@@ -92,7 +100,3 @@ function print(
 function printKeyValue(key, value) {
   return `@${key} ${value}`.trim();
 }
-
-exports.extract = extract;
-exports.parse = parse;
-exports.print = print;

From 854afa66dccfc5f60ac1713b12769b19b76489ae Mon Sep 17 00:00:00 2001
From: Lucas Azzola <derflatulator@gmail.com>
Date: Thu, 21 Sep 2017 21:51:18 +1000
Subject: [PATCH 6/8] Detect newline character, consolidate API

---
 packages/jest-docblock/README.md              |   9 +-
 packages/jest-docblock/package.json           |   5 +-
 .../jest-docblock/src/__tests__/index.test.js | 101 +++++++++++++-----
 packages/jest-docblock/src/index.js           |  34 +++---
 yarn.lock                                     |   4 +
 5 files changed, 110 insertions(+), 43 deletions(-)

diff --git a/packages/jest-docblock/README.md b/packages/jest-docblock/README.md
index 4d72b4fc2eaf..465bb3d2704d 100644
--- a/packages/jest-docblock/README.md
+++ b/packages/jest-docblock/README.md
@@ -57,7 +57,7 @@ const code = `
  }
 `;
 
-const { extract, parse, print } = require("jest-docblock");
+const { extract, parse, parseWithComments, print } = require("jest-docblock");
 
 const docblock = extract(code);
 console.log(docblock); // "/**\n * Everything is awesome!\n * \n * @everything is:awesome\n * @flow\n */"
@@ -65,7 +65,10 @@ console.log(docblock); // "/**\n * Everything is awesome!\n * \n * @everything i
 const pragmas = parse(docblock);
 console.log(pragmas); // { everything: "is:awesome", flow: "" }
 
-console.log(print(pragmas, "hi!")) // /**\n * hi!\n *\n * @everything is:awesome\n * @flow\n */;
+const parsed = parseWithComments(docblock);
+console.log(parsed); // { comments: "Everything is awesome!", pragmas: { everything: "is:awesome", flow: "" } }
+
+console.log(print({pragmas, comments: "hi!"})) // /**\n * hi!\n *\n * @everything is:awesome\n * @flow\n */;
 ```
 
 ## API Documentation
@@ -79,5 +82,5 @@ Parses the pragmas in a docblock string into an object whose keys are the pragma
 ### `parseWithComments(docblock: string): { comments: string, pragmas: {[key: string]: string} }`
 Similar to `parse` except this method also returns the comments from the docblock. Useful when used with `print()`.
 
-### `print(object: {[key: string]: string}, comments?: string): string`
+### `print({ comments: string, pragmas: {[key: string]: string} }): string`
 Prints an object of key-value pairs back into a docblock. If `comments` are provided, they will be positioned on the top of the docblock.
\ No newline at end of file
diff --git a/packages/jest-docblock/package.json b/packages/jest-docblock/package.json
index ccc2c39f7d93..04221a82d1e0 100644
--- a/packages/jest-docblock/package.json
+++ b/packages/jest-docblock/package.json
@@ -6,5 +6,8 @@
     "url": "https://github.com/facebook/jest.git"
   },
   "license": "BSD-3-Clause",
-  "main": "build/index.js"
+  "main": "build/index.js",
+  "dependencies": {
+    "detect-newline": "^2.1.0"
+  }
 }
diff --git a/packages/jest-docblock/src/__tests__/index.test.js b/packages/jest-docblock/src/__tests__/index.test.js
index e0466759429a..4ff2a42715d5 100644
--- a/packages/jest-docblock/src/__tests__/index.test.js
+++ b/packages/jest-docblock/src/__tests__/index.test.js
@@ -11,8 +11,8 @@
 
 'use strict';
 
-const os = require('os');
-const docblock = require('../');
+import os from 'os';
+import * as docblock from '..';
 
 describe('docblock', () => {
   it('extracts valid docblock with line comment', () => {
@@ -241,7 +241,7 @@ describe('docblock', () => {
       os.EOL +
       ' */';
     expect(docblock.parseWithComments(code)).toEqual({
-      comments: 'hello\nworld',
+      comments: 'hello' + os.EOL + 'world',
       pragmas: {flow: 'yes'},
     });
   });
@@ -260,37 +260,53 @@ describe('docblock', () => {
       os.EOL +
       ' */';
     expect(docblock.parseWithComments(code)).toEqual({
-      comments: 'hello\n\nworld',
+      comments: 'hello' + os.EOL + os.EOL + 'world',
       pragmas: {flow: 'yes'},
     });
   });
 
-  it('prints docblocks with no keys as empty string', () => {
-    const object = {};
-    expect(docblock.print(object)).toEqual('');
+  it('extracts docblock comments as CRLF when docblock contains CRLF', () => {
+    const code = '/**\r\n * foo\r\n * bar\r\n*/';
+    expect(docblock.parseWithComments(code)).toEqual({
+      comments: 'foo\r\nbar',
+      pragmas: {},
+    });
+  });
+
+  it('extracts docblock comments as LF when docblock contains LF', () => {
+    const code = '/**\n * foo\n * bar\n*/';
+    expect(docblock.parseWithComments(code)).toEqual({
+      comments: 'foo\nbar',
+      pragmas: {},
+    });
   });
 
-  it('prints docblocks with one key on one line', () => {
-    const object = {flow: ''};
-    expect(docblock.print(object)).toEqual('/** @flow */');
+  it('prints docblocks with no pragmas as empty string', () => {
+    const pragmas = {};
+    expect(docblock.print({pragmas})).toEqual('');
   });
 
-  it('prints docblocks with multiple keys on multiple lines', () => {
-    const object = {
+  it('prints docblocks with one pragma on one line', () => {
+    const pragmas = {flow: ''};
+    expect(docblock.print({pragmas})).toEqual('/** @flow */');
+  });
+
+  it('prints docblocks with multiple pragmas on multiple lines', () => {
+    const pragmas = {
       flow: '',
       format: '',
     };
-    expect(docblock.print(object)).toEqual(
+    expect(docblock.print({pragmas})).toEqual(
       '/**' + os.EOL + ' * @flow' + os.EOL + ' * @format' + os.EOL + ' */',
     );
   });
 
-  it('prints docblocks with values', () => {
-    const object = {
+  it('prints docblocks with pragmas', () => {
+    const pragmas = {
       flow: 'foo',
       providesModule: 'x/y/z',
     };
-    expect(docblock.print(object)).toEqual(
+    expect(docblock.print({pragmas})).toEqual(
       '/**' +
         os.EOL +
         ' * @flow foo' +
@@ -302,9 +318,9 @@ describe('docblock', () => {
   });
 
   it('prints docblocks with comments', () => {
-    const object = {flow: 'foo'};
+    const pragmas = {flow: 'foo'};
     const comments = 'hello';
-    expect(docblock.print(object, comments)).toEqual(
+    expect(docblock.print({comments, pragmas})).toEqual(
       '/**' +
         os.EOL +
         ' * hello' +
@@ -318,26 +334,61 @@ describe('docblock', () => {
   });
 
   it('prints docblocks with comments and no keys', () => {
-    const object = {};
+    const pragmas = {};
     const comments = 'Copyright 2004-present Facebook. All Rights Reserved.';
-    expect(docblock.print(object, comments)).toEqual(
+    expect(docblock.print({comments, pragmas})).toEqual(
       '/**' + os.EOL + ' * ' + comments + os.EOL + ' */',
     );
   });
 
   it('prints docblocks with multiline comments', () => {
-    const object = {};
+    const pragmas = {};
     const comments = 'hello' + os.EOL + 'world';
-    expect(docblock.print(object, comments)).toEqual(
+    expect(docblock.print({comments, pragmas})).toEqual(
       '/**' + os.EOL + ' * hello' + os.EOL + ' * world' + os.EOL + ' */',
     );
   });
 
   it('prints docblocks that are parseable', () => {
-    const object = {a: 'b', c: ''};
+    const pragmas = {a: 'b', c: ''};
     const comments = 'hello world!';
-    const formatted = docblock.print(object, comments);
+    const formatted = docblock.print({comments, pragmas});
     const parsed = docblock.parse(formatted);
-    expect(parsed).toEqual(object);
+    expect(parsed).toEqual(pragmas);
+  });
+
+  it('can augment existing docblocks with comments', () => {
+    const before =
+      '/**' + os.EOL + ' * Legalese' + os.EOL + ' * @flow' + os.EOL + ' */';
+    const parsed = docblock.parseWithComments(before);
+    parsed.pragmas.format = '';
+    const after = docblock.print(parsed);
+    expect(after).toEqual(
+      '/**' +
+        os.EOL +
+        ' * Legalese' +
+        os.EOL +
+        ' *' +
+        os.EOL +
+        ' * @flow' +
+        os.EOL +
+        ' * @format' +
+        os.EOL +
+        ' */',
+    );
+  });
+
+  it('prints docblocks using CRLF if comments contains CRLF', () => {
+    const pragmas = {};
+    const comments = 'hello\r\nworld';
+    const formatted = docblock.print({comments, pragmas});
+    expect(formatted).toEqual('/**\r\n * hello\r\n * world\r\n */');
+  });
+
+  it('prints docblocks using LF if comments contains LF', () => {
+    const pragmas = {};
+    const comments = 'hello\nworld';
+    const formatted = docblock.print({comments, pragmas});
+    expect(formatted).toEqual('/**\n * hello\n * world\n */');
   });
 });
diff --git a/packages/jest-docblock/src/index.js b/packages/jest-docblock/src/index.js
index 91f8e9dba63e..0e92f427cb5c 100644
--- a/packages/jest-docblock/src/index.js
+++ b/packages/jest-docblock/src/index.js
@@ -8,7 +8,8 @@
  * @flow
  */
 
-const os = require('os');
+import detectNewline from 'detect-newline';
+import {EOL} from 'os';
 
 const commentEndRe = /\*\/$/;
 const commentStartRe = /^\/\*\*/;
@@ -18,7 +19,7 @@ const ltrimRe = /^\s*/;
 const multilineRe = /(?:^|\r?\n) *(@[^\r\n]*?) *\r?\n *([^@\r\n\s][^@\r\n]+?) *\r?\n/g;
 const propertyRe = /(?:^|\r?\n) *@(\S+) *([^\r\n]*)/g;
 const stringStartRe = /(\r?\n|^) *\*/g;
-const lineStartRe = /(?:\r?\n|^) */g;
+const lineStartRe = /(\r?\n|^) */g;
 const wsRe = /[\t ]+/g;
 
 export function extract(contents: string): string {
@@ -33,6 +34,8 @@ export function parse(docblock: string): {[key: string]: string} {
 export function parseWithComments(
   docblock: string,
 ): {comments: string, pragmas: {[key: string]: string}} {
+  const line = detectNewline(docblock) || EOL;
+
   docblock = docblock
     .replace(commentStartRe, '')
     .replace(commentEndRe, '')
@@ -44,12 +47,12 @@ export function parseWithComments(
   let prev = '';
   while (prev !== docblock) {
     prev = docblock;
-    docblock = docblock.replace(multilineRe, '\n$1 $2\n');
+    docblock = docblock.replace(multilineRe, `${line}$1 $2${line}`);
   }
   docblock = docblock.trim();
 
   const result = Object.create(null);
-  const comments = docblock.replace(propertyRe, '').replace(lineStartRe, '\n');
+  const comments = docblock.replace(propertyRe, '').replace(lineStartRe, line);
   let match;
   while ((match = propertyRe.exec(docblock))) {
     result[match[1]] = match[2];
@@ -57,19 +60,22 @@ export function parseWithComments(
   return {comments: comments.trim(), pragmas: result};
 }
 
-export function print(
-  object: {[key: string]: string} = {},
-  comments: string = '',
-): string {
+export function print({
+  comments = '',
+  pragmas = {},
+}: {
+  comments: string,
+  pragmas: {[key: string]: string},
+}): string {
+  const line = detectNewline(comments) || EOL;
   const head = '/**';
   const start = ' *';
   const tail = ' */';
 
-  const keys = Object.keys(object);
-  const line = os.EOL;
+  const keys = Object.keys(pragmas);
 
   const printedObject = keys
-    .map(key => start + ' ' + printKeyValue(key, object[key]) + line)
+    .map(key => start + ' ' + printKeyValue(key, pragmas[key]) + line)
     .join('');
 
   if (!comments) {
@@ -77,15 +83,15 @@ export function print(
       return '';
     }
     if (keys.length === 1) {
-      return `${head} ${printKeyValue(keys[0], object[keys[0]])}${tail}`;
+      return `${head} ${printKeyValue(keys[0], pragmas[keys[0]])}${tail}`;
     }
   }
 
   const printedComments =
     comments
-      .split(os.EOL)
+      .split(line)
       .map(textLine => `${start} ${textLine}`)
-      .join(os.EOL) + os.EOL;
+      .join(line) + line;
 
   return (
     head +
diff --git a/yarn.lock b/yarn.lock
index e3aee5cc88cd..360a7f0d8c90 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1971,6 +1971,10 @@ detect-indent@^5.0.0:
   version "5.0.0"
   resolved "https://registry.yarnpkg.com/detect-indent/-/detect-indent-5.0.0.tgz#3871cc0a6a002e8c3e5b3cf7f336264675f06b9d"
 
+detect-newline@^2.1.0:
+  version "2.1.0"
+  resolved "https://registry.yarnpkg.com/detect-newline/-/detect-newline-2.1.0.tgz#f41f1c10be4b00e87b5f13da680759f2c5bfd3e2"
+
 detective@^4.0.0:
   version "4.5.0"
   resolved "https://registry.yarnpkg.com/detective/-/detective-4.5.0.tgz#6e5a8c6b26e6c7a254b1c6b6d7490d98ec91edd1"

From dc34f5ddbf8c0f40a8fc9a14829f3410577ee4bd Mon Sep 17 00:00:00 2001
From: Lucas Azzola <derflatulator@gmail.com>
Date: Thu, 21 Sep 2017 22:21:01 +1000
Subject: [PATCH 7/8] Fixup types

---
 packages/jest-docblock/README.md                   | 2 +-
 packages/jest-docblock/src/__tests__/index.test.js | 6 +++---
 packages/jest-docblock/src/index.js                | 6 ++++--
 3 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/packages/jest-docblock/README.md b/packages/jest-docblock/README.md
index 465bb3d2704d..85a740b8e6aa 100644
--- a/packages/jest-docblock/README.md
+++ b/packages/jest-docblock/README.md
@@ -82,5 +82,5 @@ Parses the pragmas in a docblock string into an object whose keys are the pragma
 ### `parseWithComments(docblock: string): { comments: string, pragmas: {[key: string]: string} }`
 Similar to `parse` except this method also returns the comments from the docblock. Useful when used with `print()`.
 
-### `print({ comments: string, pragmas: {[key: string]: string} }): string`
+### `print({ comments?: string, pragmas?: {[key: string]: string} }): string`
 Prints an object of key-value pairs back into a docblock. If `comments` are provided, they will be positioned on the top of the docblock.
\ No newline at end of file
diff --git a/packages/jest-docblock/src/__tests__/index.test.js b/packages/jest-docblock/src/__tests__/index.test.js
index 4ff2a42715d5..ce248386a8ce 100644
--- a/packages/jest-docblock/src/__tests__/index.test.js
+++ b/packages/jest-docblock/src/__tests__/index.test.js
@@ -360,9 +360,9 @@ describe('docblock', () => {
   it('can augment existing docblocks with comments', () => {
     const before =
       '/**' + os.EOL + ' * Legalese' + os.EOL + ' * @flow' + os.EOL + ' */';
-    const parsed = docblock.parseWithComments(before);
-    parsed.pragmas.format = '';
-    const after = docblock.print(parsed);
+    const {comments, pragmas} = docblock.parseWithComments(before);
+    pragmas.format = '';
+    const after = docblock.print({comments, pragmas});
     expect(after).toEqual(
       '/**' +
         os.EOL +
diff --git a/packages/jest-docblock/src/index.js b/packages/jest-docblock/src/index.js
index 0e92f427cb5c..e5ee76751349 100644
--- a/packages/jest-docblock/src/index.js
+++ b/packages/jest-docblock/src/index.js
@@ -64,8 +64,8 @@ export function print({
   comments = '',
   pragmas = {},
 }: {
-  comments: string,
-  pragmas: {[key: string]: string},
+  comments?: string,
+  pragmas?: {[key: string]: string},
 }): string {
   const line = detectNewline(comments) || EOL;
   const head = '/**';
@@ -106,3 +106,5 @@ export function print({
 function printKeyValue(key, value) {
   return `@${key} ${value}`.trim();
 }
+
+export default {extract, parse, parseWithComments, print};

From a13f950da9414f3c541a6970e5b6a25051b0cae1 Mon Sep 17 00:00:00 2001
From: Lucas Azzola <derflatulator@gmail.com>
Date: Fri, 22 Sep 2017 20:54:23 +1000
Subject: [PATCH 8/8] Remove default export from jest-docblock

BREAKING CHANGE: Changes jest-docblock to an ES module without a default export,
requires `import * as docblock from 'jest-docbloc'`
---
 packages/jest-docblock/src/index.js   | 2 --
 packages/jest-haste-map/src/worker.js | 2 +-
 packages/jest-runner/src/run_test.js  | 2 +-
 3 files changed, 2 insertions(+), 4 deletions(-)

diff --git a/packages/jest-docblock/src/index.js b/packages/jest-docblock/src/index.js
index e5ee76751349..6e43729909a6 100644
--- a/packages/jest-docblock/src/index.js
+++ b/packages/jest-docblock/src/index.js
@@ -106,5 +106,3 @@ export function print({
 function printKeyValue(key, value) {
   return `@${key} ${value}`.trim();
 }
-
-export default {extract, parse, parseWithComments, print};
diff --git a/packages/jest-haste-map/src/worker.js b/packages/jest-haste-map/src/worker.js
index 451f2ee36eaa..67c457451213 100644
--- a/packages/jest-haste-map/src/worker.js
+++ b/packages/jest-haste-map/src/worker.js
@@ -12,7 +12,7 @@ import type {SerializableError} from 'types/TestResult';
 import type {HasteImpl, WorkerMessage, WorkerCallback} from './types';
 
 import path from 'path';
-import docblock from 'jest-docblock';
+import * as docblock from 'jest-docblock';
 import fs from 'graceful-fs';
 import H from './constants';
 import extractRequires from './lib/extract_requires';
diff --git a/packages/jest-runner/src/run_test.js b/packages/jest-runner/src/run_test.js
index ed5b35f52fe3..a0ad0d84821d 100644
--- a/packages/jest-runner/src/run_test.js
+++ b/packages/jest-runner/src/run_test.js
@@ -25,7 +25,7 @@ import {
 } from 'jest-util';
 import jasmine2 from 'jest-jasmine2';
 import {getTestEnvironment} from 'jest-config';
-import docblock from 'jest-docblock';
+import * as docblock from 'jest-docblock';
 
 // The default jest-runner is required because it is the default test runner
 // and required implicitly through the `testRunner` ProjectConfig option.