From 6b8c6078f87ad97f7c11567bb6946df35a4a9846 Mon Sep 17 00:00:00 2001
From: Connor Clark <cjamcl@google.com>
Date: Sat, 11 May 2019 11:53:33 -0700
Subject: [PATCH 01/12] cli: accept csv for array values

---
 lighthouse-cli/cli-flags.js               | 34 ++++++++++++++++++++---
 lighthouse-cli/test/cli/cli-flags-test.js | 10 +++++++
 2 files changed, 40 insertions(+), 4 deletions(-)

diff --git a/lighthouse-cli/cli-flags.js b/lighthouse-cli/cli-flags.js
index 06e96f93dab2..4a7bc04fe953 100644
--- a/lighthouse-cli/cli-flags.js
+++ b/lighthouse-cli/cli-flags.js
@@ -12,12 +12,21 @@ const pkg = require('../package.json');
 const printer = require('./printer');
 
 /**
- * @param {string=} manualArgv
+ * @param {(string | string[])[]} arr
+ * @return {string[]}
+ */
+function flatten(arr) {
+  /** @type {string[]} */
+  const result = [];
+  return result.concat(...arr);
+}
+
+/**
+ * @param {string[]} manualArgv
  * @return {LH.CliFlags}
  */
-function getFlags(manualArgv) {
-  // @ts-ignore yargs() is incorrectly typed as not returning itself
-  const y = manualArgv ? yargs(manualArgv) : yargs;
+function getFlags(...manualArgv) {
+  const y = manualArgv.length ? yargs(manualArgv) : yargs;
   return y.help('help')
       .version(() => pkg.version)
       .showHelpOnFail(false, 'Specify --help for available options')
@@ -152,6 +161,23 @@ function getFlags(manualArgv) {
       .default('enable-error-reporting', undefined) // Undefined so prompted by default
       .default('channel', 'cli')
       .check(/** @param {LH.CliFlags} argv */ (argv) => {
+        // ".middleware" does not exist in this version of yargs, so do some preprocessing here.
+        /** @type {(keyof LH.CliFlags)[]} */
+        const arrayKeys = [
+          'blockedUrlPatterns',
+          'onlyAudits',
+          'onlyCategories',
+          'skipAudits',
+          'output',
+          'plugins',
+        ];
+        arrayKeys.forEach(key => {
+          const input = /** @type {string[]} */ (argv[key]);
+          if (input) {
+            argv[key] = flatten(input.map(value => value.split(',')));
+          }
+        });
+
         // Lighthouse doesn't need a URL if...
         //   - We're just listing the available options.
         //   - We're just printing the config.
diff --git a/lighthouse-cli/test/cli/cli-flags-test.js b/lighthouse-cli/test/cli/cli-flags-test.js
index 99e676e37551..284a10fb0f06 100644
--- a/lighthouse-cli/test/cli/cli-flags-test.js
+++ b/lighthouse-cli/test/cli/cli-flags-test.js
@@ -28,4 +28,14 @@ describe('CLI bin', function() {
       assert.ok(optionsWithDescriptions.includes(opt), `cli option '${opt}' has no description`);
     });
   });
+
+  it('array values support csv', () => {
+    const flags = getFlags(
+      'http://www.example.com',
+      '--only-categories=performance,seo',
+      '--skipAudits=unused-javascript,redirects',
+      '--skipAudits=bootup-time');
+    expect(flags.onlyCategories).toEqual(['performance', 'seo']);
+    expect(flags.skipAudits).toEqual(['unused-javascript', 'redirects', 'bootup-time']);
+  });
 });

From 9fe961a8343a859293847e9f8ee00b92d02f1953 Mon Sep 17 00:00:00 2001
From: Connor Clark <cjamcl@google.com>
Date: Sat, 11 May 2019 12:40:59 -0700
Subject: [PATCH 02/12] dont hardcode list of array keys

---
 lighthouse-cli/cli-flags.js | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/lighthouse-cli/cli-flags.js b/lighthouse-cli/cli-flags.js
index 4a7bc04fe953..25bf5794102e 100644
--- a/lighthouse-cli/cli-flags.js
+++ b/lighthouse-cli/cli-flags.js
@@ -162,21 +162,15 @@ function getFlags(...manualArgv) {
       .default('channel', 'cli')
       .check(/** @param {LH.CliFlags} argv */ (argv) => {
         // ".middleware" does not exist in this version of yargs, so do some preprocessing here.
-        /** @type {(keyof LH.CliFlags)[]} */
-        const arrayKeys = [
-          'blockedUrlPatterns',
-          'onlyAudits',
-          'onlyCategories',
-          'skipAudits',
-          'output',
-          'plugins',
-        ];
-        arrayKeys.forEach(key => {
-          const input = /** @type {string[]} */ (argv[key]);
-          if (input) {
-            argv[key] = flatten(input.map(value => value.split(',')));
+        for (const _key of Object.keys(argv)) {
+          const key = /** @type {keyof argv} */ (_key);
+          const input = argv[key];
+          if (Array.isArray(input)) {
+            // These values are guarenteed to be strings.
+            const strings = /** @type {string[]} */ (input);
+            argv[key] = flatten(strings.map(value => value.split(',')));
           }
-        });
+        }
 
         // Lighthouse doesn't need a URL if...
         //   - We're just listing the available options.

From 35e2f017fb4bea22e63fde81e05669caf7d6bca1 Mon Sep 17 00:00:00 2001
From: Connor Clark <cjamcl@google.com>
Date: Mon, 13 May 2019 11:51:47 -0700
Subject: [PATCH 03/12] Revert "dont hardcode list of array keys"

This reverts commit 9fe961a8343a859293847e9f8ee00b92d02f1953.
---
 lighthouse-cli/cli-flags.js | 22 ++++++++++++++--------
 1 file changed, 14 insertions(+), 8 deletions(-)

diff --git a/lighthouse-cli/cli-flags.js b/lighthouse-cli/cli-flags.js
index 25bf5794102e..4a7bc04fe953 100644
--- a/lighthouse-cli/cli-flags.js
+++ b/lighthouse-cli/cli-flags.js
@@ -162,15 +162,21 @@ function getFlags(...manualArgv) {
       .default('channel', 'cli')
       .check(/** @param {LH.CliFlags} argv */ (argv) => {
         // ".middleware" does not exist in this version of yargs, so do some preprocessing here.
-        for (const _key of Object.keys(argv)) {
-          const key = /** @type {keyof argv} */ (_key);
-          const input = argv[key];
-          if (Array.isArray(input)) {
-            // These values are guarenteed to be strings.
-            const strings = /** @type {string[]} */ (input);
-            argv[key] = flatten(strings.map(value => value.split(',')));
+        /** @type {(keyof LH.CliFlags)[]} */
+        const arrayKeys = [
+          'blockedUrlPatterns',
+          'onlyAudits',
+          'onlyCategories',
+          'skipAudits',
+          'output',
+          'plugins',
+        ];
+        arrayKeys.forEach(key => {
+          const input = /** @type {string[]} */ (argv[key]);
+          if (input) {
+            argv[key] = flatten(input.map(value => value.split(',')));
           }
-        }
+        });
 
         // Lighthouse doesn't need a URL if...
         //   - We're just listing the available options.

From 879b2881847914a028e791cd1b4a9de91504ca25 Mon Sep 17 00:00:00 2001
From: Connor Clark <cjamcl@google.com>
Date: Mon, 13 May 2019 11:52:21 -0700
Subject: [PATCH 04/12] add tests for csv whitelist

---
 lighthouse-cli/cli-flags.js               |  3 +--
 lighthouse-cli/test/cli/cli-flags-test.js | 12 +++++++++++-
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/lighthouse-cli/cli-flags.js b/lighthouse-cli/cli-flags.js
index 4a7bc04fe953..198dad55f398 100644
--- a/lighthouse-cli/cli-flags.js
+++ b/lighthouse-cli/cli-flags.js
@@ -164,12 +164,11 @@ function getFlags(...manualArgv) {
         // ".middleware" does not exist in this version of yargs, so do some preprocessing here.
         /** @type {(keyof LH.CliFlags)[]} */
         const arrayKeys = [
-          'blockedUrlPatterns',
           'onlyAudits',
           'onlyCategories',
-          'skipAudits',
           'output',
           'plugins',
+          'skipAudits',
         ];
         arrayKeys.forEach(key => {
           const input = /** @type {string[]} */ (argv[key]);
diff --git a/lighthouse-cli/test/cli/cli-flags-test.js b/lighthouse-cli/test/cli/cli-flags-test.js
index 284a10fb0f06..2990f4da5b0d 100644
--- a/lighthouse-cli/test/cli/cli-flags-test.js
+++ b/lighthouse-cli/test/cli/cli-flags-test.js
@@ -29,7 +29,7 @@ describe('CLI bin', function() {
     });
   });
 
-  it('array values support csv', () => {
+  it('array values support csv when appropriate', () => {
     const flags = getFlags(
       'http://www.example.com',
       '--only-categories=performance,seo',
@@ -38,4 +38,14 @@ describe('CLI bin', function() {
     expect(flags.onlyCategories).toEqual(['performance', 'seo']);
     expect(flags.skipAudits).toEqual(['unused-javascript', 'redirects', 'bootup-time']);
   });
+
+  it('array values do not support csv when appropriate', () => {
+    const flags = getFlags(
+      'http://www.example.com',
+      '--chrome-flags="--window-size 800,600"',
+      '--chrome-flags="--enabled-features=NetworkService,VirtualTime"',
+      '--blockedUrlPatterns=.*x,y\\.png');
+    expect(flags.chromeFlags).toEqual(['"--window-size 800,600"', '"--enabled-features=NetworkService,VirtualTime"']);
+    expect(flags.blockedUrlPatterns).toEqual(['.*x,y\\.png']);
+  });
 });

From 3e3cc4c4e32911fea97f016908dcd2ae7b22b64e Mon Sep 17 00:00:00 2001
From: Connor Clark <cjamcl@google.com>
Date: Mon, 13 May 2019 14:56:33 -0700
Subject: [PATCH 05/12] lint, move out of .check

---
 lighthouse-cli/cli-flags.js               | 37 ++++++++++++-----------
 lighthouse-cli/test/cli/cli-flags-test.js |  5 ++-
 2 files changed, 24 insertions(+), 18 deletions(-)

diff --git a/lighthouse-cli/cli-flags.js b/lighthouse-cli/cli-flags.js
index 198dad55f398..bafb5e9e2824 100644
--- a/lighthouse-cli/cli-flags.js
+++ b/lighthouse-cli/cli-flags.js
@@ -27,7 +27,8 @@ function flatten(arr) {
  */
 function getFlags(...manualArgv) {
   const y = manualArgv.length ? yargs(manualArgv) : yargs;
-  return y.help('help')
+  /** @type {LH.CliFlags} */
+  const argv = y.help('help')
       .version(() => pkg.version)
       .showHelpOnFail(false, 'Specify --help for available options')
 
@@ -161,22 +162,6 @@ function getFlags(...manualArgv) {
       .default('enable-error-reporting', undefined) // Undefined so prompted by default
       .default('channel', 'cli')
       .check(/** @param {LH.CliFlags} argv */ (argv) => {
-        // ".middleware" does not exist in this version of yargs, so do some preprocessing here.
-        /** @type {(keyof LH.CliFlags)[]} */
-        const arrayKeys = [
-          'onlyAudits',
-          'onlyCategories',
-          'output',
-          'plugins',
-          'skipAudits',
-        ];
-        arrayKeys.forEach(key => {
-          const input = /** @type {string[]} */ (argv[key]);
-          if (input) {
-            argv[key] = flatten(input.map(value => value.split(',')));
-          }
-        });
-
         // Lighthouse doesn't need a URL if...
         //   - We're just listing the available options.
         //   - We're just printing the config.
@@ -196,6 +181,24 @@ function getFlags(...manualArgv) {
           'For more information on Lighthouse, see https://developers.google.com/web/tools/lighthouse/.')
       .wrap(yargs.terminalWidth())
       .argv;
+
+  // ".middleware" does not exist in this version of yargs, so do some post-processing here.
+  /** @type {(keyof LH.CliFlags)[]} */
+  const arrayKeysThatSupportCsv = [
+    'onlyAudits',
+    'onlyCategories',
+    'output',
+    'plugins',
+    'skipAudits',
+  ];
+  arrayKeysThatSupportCsv.forEach(key => {
+    const input = /** @type {string[]} */ (argv[key]);
+    if (input) {
+      argv[key] = flatten(input.map(value => value.split(',')));
+    }
+  });
+
+  return argv;
 }
 
 module.exports = {
diff --git a/lighthouse-cli/test/cli/cli-flags-test.js b/lighthouse-cli/test/cli/cli-flags-test.js
index 2990f4da5b0d..b419b0ec77f3 100644
--- a/lighthouse-cli/test/cli/cli-flags-test.js
+++ b/lighthouse-cli/test/cli/cli-flags-test.js
@@ -45,7 +45,10 @@ describe('CLI bin', function() {
       '--chrome-flags="--window-size 800,600"',
       '--chrome-flags="--enabled-features=NetworkService,VirtualTime"',
       '--blockedUrlPatterns=.*x,y\\.png');
-    expect(flags.chromeFlags).toEqual(['"--window-size 800,600"', '"--enabled-features=NetworkService,VirtualTime"']);
+    expect(flags.chromeFlags).toEqual([
+      '"--window-size 800,600"',
+      '"--enabled-features=NetworkService,VirtualTime"',
+    ]);
     expect(flags.blockedUrlPatterns).toEqual(['.*x,y\\.png']);
   });
 });

From ee443608b6b47895148dc664bb635997aab1d20d Mon Sep 17 00:00:00 2001
From: Connor Clark <cjamcl@google.com>
Date: Mon, 13 May 2019 15:11:10 -0700
Subject: [PATCH 06/12] add example

---
 lighthouse-cli/cli-flags.js | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/lighthouse-cli/cli-flags.js b/lighthouse-cli/cli-flags.js
index bafb5e9e2824..8331800471d7 100644
--- a/lighthouse-cli/cli-flags.js
+++ b/lighthouse-cli/cli-flags.js
@@ -35,6 +35,9 @@ function getFlags(...manualArgv) {
       .usage('lighthouse <url> <options>')
       .example(
           'lighthouse <url> --view', 'Opens the HTML report in a browser after the run completes')
+      .example(
+          'lighthouse <url> --only-categories=performance,pwa',
+          'Only run specific categories.')
       .example(
           'lighthouse <url> --config-path=./myconfig.js',
           'Runs Lighthouse with your own configuration: custom audits, report generation, etc.')
@@ -183,7 +186,7 @@ function getFlags(...manualArgv) {
       .argv;
 
   // ".middleware" does not exist in this version of yargs, so do some post-processing here.
-  /** @type {(keyof LH.CliFlags)[]} */
+  /** @type {Array<keyof LH.CliFlags>} */
   const arrayKeysThatSupportCsv = [
     'onlyAudits',
     'onlyCategories',

From 0d1a6113ef1da2091848c2c6abbac60ad2f5b198 Mon Sep 17 00:00:00 2001
From: Connor Clark <cjamcl@google.com>
Date: Thu, 16 May 2019 12:59:08 -0700
Subject: [PATCH 07/12] move example down, revise param type for flatten

---
 lighthouse-cli/cli-flags.js | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/lighthouse-cli/cli-flags.js b/lighthouse-cli/cli-flags.js
index 8331800471d7..e633f62838c8 100644
--- a/lighthouse-cli/cli-flags.js
+++ b/lighthouse-cli/cli-flags.js
@@ -12,7 +12,8 @@ const pkg = require('../package.json');
 const printer = require('./printer');
 
 /**
- * @param {(string | string[])[]} arr
+ * Remove in Node 11 - [].flatMap
+ * @param {Array<Array<string>>} arr
  * @return {string[]}
  */
 function flatten(arr) {
@@ -35,9 +36,6 @@ function getFlags(...manualArgv) {
       .usage('lighthouse <url> <options>')
       .example(
           'lighthouse <url> --view', 'Opens the HTML report in a browser after the run completes')
-      .example(
-          'lighthouse <url> --only-categories=performance,pwa',
-          'Only run specific categories.')
       .example(
           'lighthouse <url> --config-path=./myconfig.js',
           'Runs Lighthouse with your own configuration: custom audits, report generation, etc.')
@@ -59,6 +57,9 @@ function getFlags(...manualArgv) {
       .example(
           'lighthouse <url> --extra-headers=./path/to/file.json',
           'Path to JSON file of HTTP Header key/value pairs to send in requests')
+      .example(
+          'lighthouse <url> --only-categories=performance,pwa',
+          'Only run specific categories.')
 
       // List of options
       .group(['verbose', 'quiet'], 'Logging:')

From 0067f008c6d441501f8957736e5aa36a673a6841 Mon Sep 17 00:00:00 2001
From: Connor Clark <cjamcl@google.com>
Date: Thu, 16 May 2019 13:02:13 -0700
Subject: [PATCH 08/12] add comment

---
 lighthouse-cli/cli-flags.js | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/lighthouse-cli/cli-flags.js b/lighthouse-cli/cli-flags.js
index e633f62838c8..c78e78ddae65 100644
--- a/lighthouse-cli/cli-flags.js
+++ b/lighthouse-cli/cli-flags.js
@@ -196,6 +196,8 @@ function getFlags(...manualArgv) {
     'skipAudits',
   ];
   arrayKeysThatSupportCsv.forEach(key => {
+    // If a key is defined as an array in yargs, the value (if provided)
+    // will always be a string array.
     const input = /** @type {string[]} */ (argv[key]);
     if (input) {
       argv[key] = flatten(input.map(value => value.split(',')));

From 6f58b9007f2b9be45e7a399187b7d07b3d46554c Mon Sep 17 00:00:00 2001
From: Connor Clark <cjamcl@google.com>
Date: Thu, 16 May 2019 13:09:08 -0700
Subject: [PATCH 09/12] fix run test

---
 lighthouse-cli/test/cli/run-test.js | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/lighthouse-cli/test/cli/run-test.js b/lighthouse-cli/test/cli/run-test.js
index 7c00cf961ba4..40c56889baf6 100644
--- a/lighthouse-cli/test/cli/run-test.js
+++ b/lighthouse-cli/test/cli/run-test.js
@@ -39,8 +39,12 @@ describe('CLI run', function() {
       const timeoutFlag = `--max-wait-for-load=${9000}`;
       const pluginsFlag = '--plugins=lighthouse-plugin-simple';
 
-      // eslint-disable-next-line max-len
-      const flags = getFlags(`--output=json --output-path=${filename} ${pluginsFlag} ${timeoutFlag} ${url}`);
+      const flags = getFlags(
+        '--output=json',
+         `--output-path=${filename}`,
+        pluginsFlag,
+        timeoutFlag,
+        url);
 
       const rawResult = await run.runLighthouse(url, flags, fastConfig);
 
@@ -90,7 +94,7 @@ describe('CLI run', function() {
 
 describe('flag coercing', () => {
   it('should force to array', () => {
-    assert.deepStrictEqual(getFlags(`--only-audits foo chrome://version`).onlyAudits, ['foo']);
+    assert.deepStrictEqual(getFlags('--only-audits=foo', 'chrome://version').onlyAudits, ['foo']);
   });
 });
 

From e4da3a9f2ecd069281ff4415b05f179216bf345b Mon Sep 17 00:00:00 2001
From: Connor Clark <cjamcl@google.com>
Date: Thu, 16 May 2019 19:08:07 -0700
Subject: [PATCH 10/12] revert getFlags param change

---
 lighthouse-cli/cli-flags.js               | 17 ++++++++++-------
 lighthouse-cli/test/cli/cli-flags-test.js | 14 ++++++++------
 lighthouse-cli/test/cli/run-test.js       | 10 +++-------
 3 files changed, 21 insertions(+), 20 deletions(-)

diff --git a/lighthouse-cli/cli-flags.js b/lighthouse-cli/cli-flags.js
index c78e78ddae65..485a5817eef7 100644
--- a/lighthouse-cli/cli-flags.js
+++ b/lighthouse-cli/cli-flags.js
@@ -23,12 +23,12 @@ function flatten(arr) {
 }
 
 /**
- * @param {string[]} manualArgv
+ * @param {string=} manualArgv
  * @return {LH.CliFlags}
  */
-function getFlags(...manualArgv) {
-  const y = manualArgv.length ? yargs(manualArgv) : yargs;
-  /** @type {LH.CliFlags} */
+function getFlags(manualArgv) {
+  // @ts-ignore yargs() is incorrectly typed as not returning itself
+  const y = manualArgv ? yargs(manualArgv) : yargs;
   const argv = y.help('help')
       .version(() => pkg.version)
       .showHelpOnFail(false, 'Specify --help for available options')
@@ -197,9 +197,12 @@ function getFlags(...manualArgv) {
   ];
   arrayKeysThatSupportCsv.forEach(key => {
     // If a key is defined as an array in yargs, the value (if provided)
-    // will always be a string array.
-    const input = /** @type {string[]} */ (argv[key]);
-    if (input) {
+    // will always be a string array. However, we keep argv and input as any,
+    // since assigning back to argv as string[] would be unsound for enums,
+    // for example: output is LH.OutputMode[].
+    const input = argv[key];
+    // Existence check + convinces TS that this is an array.
+    if (Array.isArray(input)) {
       argv[key] = flatten(input.map(value => value.split(',')));
     }
   });
diff --git a/lighthouse-cli/test/cli/cli-flags-test.js b/lighthouse-cli/test/cli/cli-flags-test.js
index b419b0ec77f3..da55490120d6 100644
--- a/lighthouse-cli/test/cli/cli-flags-test.js
+++ b/lighthouse-cli/test/cli/cli-flags-test.js
@@ -30,24 +30,26 @@ describe('CLI bin', function() {
   });
 
   it('array values support csv when appropriate', () => {
-    const flags = getFlags(
+    const flags = getFlags([
       'http://www.example.com',
       '--only-categories=performance,seo',
       '--skipAudits=unused-javascript,redirects',
-      '--skipAudits=bootup-time');
+      '--skipAudits=bootup-time',
+    ].join(' '));
     expect(flags.onlyCategories).toEqual(['performance', 'seo']);
     expect(flags.skipAudits).toEqual(['unused-javascript', 'redirects', 'bootup-time']);
   });
 
   it('array values do not support csv when appropriate', () => {
-    const flags = getFlags(
+    const flags = getFlags([
       'http://www.example.com',
       '--chrome-flags="--window-size 800,600"',
       '--chrome-flags="--enabled-features=NetworkService,VirtualTime"',
-      '--blockedUrlPatterns=.*x,y\\.png');
+      '--blockedUrlPatterns=.*x,y\\.png',
+    ].join(' '));
     expect(flags.chromeFlags).toEqual([
-      '"--window-size 800,600"',
-      '"--enabled-features=NetworkService,VirtualTime"',
+      '--window-size 800,600',
+      '--enabled-features=NetworkService,VirtualTime',
     ]);
     expect(flags.blockedUrlPatterns).toEqual(['.*x,y\\.png']);
   });
diff --git a/lighthouse-cli/test/cli/run-test.js b/lighthouse-cli/test/cli/run-test.js
index 40c56889baf6..7c00cf961ba4 100644
--- a/lighthouse-cli/test/cli/run-test.js
+++ b/lighthouse-cli/test/cli/run-test.js
@@ -39,12 +39,8 @@ describe('CLI run', function() {
       const timeoutFlag = `--max-wait-for-load=${9000}`;
       const pluginsFlag = '--plugins=lighthouse-plugin-simple';
 
-      const flags = getFlags(
-        '--output=json',
-         `--output-path=${filename}`,
-        pluginsFlag,
-        timeoutFlag,
-        url);
+      // eslint-disable-next-line max-len
+      const flags = getFlags(`--output=json --output-path=${filename} ${pluginsFlag} ${timeoutFlag} ${url}`);
 
       const rawResult = await run.runLighthouse(url, flags, fastConfig);
 
@@ -94,7 +90,7 @@ describe('CLI run', function() {
 
 describe('flag coercing', () => {
   it('should force to array', () => {
-    assert.deepStrictEqual(getFlags('--only-audits=foo', 'chrome://version').onlyAudits, ['foo']);
+    assert.deepStrictEqual(getFlags(`--only-audits foo chrome://version`).onlyAudits, ['foo']);
   });
 });
 

From d49db90d5a9a6321741b1b90d19333e1127c6bfd Mon Sep 17 00:00:00 2001
From: cjamcl <cjamcl@gmail.com>
Date: Mon, 20 May 2019 14:00:30 -0700
Subject: [PATCH 11/12] Update lighthouse-cli/cli-flags.js

Co-Authored-By: Brendan Kenny <bckenny@gmail.com>
---
 lighthouse-cli/cli-flags.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lighthouse-cli/cli-flags.js b/lighthouse-cli/cli-flags.js
index 485a5817eef7..39869de03eb6 100644
--- a/lighthouse-cli/cli-flags.js
+++ b/lighthouse-cli/cli-flags.js
@@ -186,7 +186,7 @@ function getFlags(manualArgv) {
       .wrap(yargs.terminalWidth())
       .argv;
 
-  // ".middleware" does not exist in this version of yargs, so do some post-processing here.
+  // Support comma-separated values for some array flags by splitting on any ',' found.
   /** @type {Array<keyof LH.CliFlags>} */
   const arrayKeysThatSupportCsv = [
     'onlyAudits',

From 2b46961b7a286206fa39cf3c2f399bc850538e7d Mon Sep 17 00:00:00 2001
From: Connor Clark <cjamcl@google.com>
Date: Mon, 20 May 2019 14:04:17 -0700
Subject: [PATCH 12/12] edit comments

---
 lighthouse-cli/cli-flags.js | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/lighthouse-cli/cli-flags.js b/lighthouse-cli/cli-flags.js
index 39869de03eb6..28f6036424e6 100644
--- a/lighthouse-cli/cli-flags.js
+++ b/lighthouse-cli/cli-flags.js
@@ -27,8 +27,9 @@ function flatten(arr) {
  * @return {LH.CliFlags}
  */
 function getFlags(manualArgv) {
-  // @ts-ignore yargs() is incorrectly typed as not returning itself
+  // @ts-ignore yargs() is incorrectly typed as not accepting a single string.
   const y = manualArgv ? yargs(manualArgv) : yargs;
+  // Intentionally left as type `any` because @types/yargs doesn't chain correctly.
   const argv = y.help('help')
       .version(() => pkg.version)
       .showHelpOnFail(false, 'Specify --help for available options')
@@ -201,7 +202,7 @@ function getFlags(manualArgv) {
     // since assigning back to argv as string[] would be unsound for enums,
     // for example: output is LH.OutputMode[].
     const input = argv[key];
-    // Existence check + convinces TS that this is an array.
+    // Truthy check is necessary. isArray convinces TS that this is an array.
     if (Array.isArray(input)) {
       argv[key] = flatten(input.map(value => value.split(',')));
     }