diff --git a/.circleci/config.yml b/.circleci/config.yml
index 6f61ffbc6f..b6b5065b71 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -278,7 +278,7 @@ jobs:
       - run: 'yarn bazel:lint ||
               (echo -e "\n.bzl files have lint errors. Please run ''yarn bazel:lint-fix''"; exit 1)'
 
-      - run: yarn lint
+      - run: yarn lint --branch $CI_GIT_BASE_REVISION
       - run: yarn ts-circular-deps:check
       - run: yarn -s ng-dev pullapprove:verify
 
diff --git a/.circleci/env.sh b/.circleci/env.sh
index 84affc8b57..7c65f56ddf 100755
--- a/.circleci/env.sh
+++ b/.circleci/env.sh
@@ -30,6 +30,8 @@ else
   setPublicVar CI_COMMIT "$CIRCLE_SHA1";
   # `CI_COMMIT_RANGE` is only used on push builds (a.k.a. non-PR, non-scheduled builds and rerun
   # workflows of such builds).
+  setPublicVar CI_GIT_BASE_REVISION "${CIRCLE_GIT_BASE_REVISION}";
+  setPublicVar CI_GIT_REVISION "${CIRCLE_GIT_REVISION}";
   setPublicVar CI_COMMIT_RANGE "$CIRCLE_GIT_BASE_REVISION..$CIRCLE_GIT_REVISION";
   setPublicVar CI_PULL_REQUEST "${CIRCLE_PR_NUMBER:-false}";
   setPublicVar CI_REPO_NAME "$CIRCLE_PROJECT_REPONAME";
diff --git a/gulpfile.js b/gulpfile.js
index 49157e466e..35852b3103 100644
--- a/gulpfile.js
+++ b/gulpfile.js
@@ -26,26 +26,30 @@ function loadTask(fileName, taskName) {
   return task(gulp);
 }
 
-// Check source code for formatting errors in all source files.
-gulp.task('format:enforce', loadTask('format', 'enforce'));
+//#######################################################
+// A format and enforce task for different sets of files.
+//#######################################################
 
-// Format all source files.
+// All source files.
 gulp.task('format:all', loadTask('format', 'format'));
+gulp.task('format:all:enforce', loadTask('format', 'enforce'));
 
-// Format only untracked source code files.
+// Untracked source code files.
 gulp.task('format:untracked', loadTask('format', 'format-untracked'));
+gulp.task('format:untracked:enforce', loadTask('format', 'enforce-untracked'));
 
-// Format only the changed, tracked source code files.
+// Changed, tracked source code files.
 gulp.task('format:diff', loadTask('format', 'format-diff'));
+gulp.task('format:diff:enforce', loadTask('format', 'enforce-diff'));
 
-// Format only changed lines based on the diff from the provided --branch
-// argument (or `master` by default).
+// Changed, both tracked and untracked, source code files.
 gulp.task('format:changed', ['format:untracked', 'format:diff']);
+gulp.task('format:changed:enforce', ['format:untracked:enforce', 'format:diff:enforce']);
 
 // Alias for `format:changed` that formerly formatted all files.
 gulp.task('format', ['format:changed']);
 
-gulp.task('lint', ['format:enforce', 'validate-commit-messages']);
+gulp.task('lint', ['format:changed:enforce', 'validate-commit-messages']);
 gulp.task('validate-commit-messages', loadTask('validate-commit-message'));
 gulp.task('source-map-test', loadTask('source-map-test'));
 gulp.task('changelog', loadTask('changelog'));
diff --git a/package.json b/package.json
index 52317d0147..d485e098e5 100644
--- a/package.json
+++ b/package.json
@@ -157,7 +157,7 @@
     "@yarnpkg/lockfile": "^1.1.0",
     "browserstacktunnel-wrapper": "2.0.1",
     "check-side-effects": "0.0.21",
-    "clang-format": "1.0.41",
+    "clang-format": "^1.4.0",
     "cldr": "4.10.0",
     "cldr-data": "36.0.0",
     "cldrjs": "0.5.0",
@@ -167,7 +167,7 @@
     "firefox-profile": "1.0.3",
     "glob": "7.1.2",
     "gulp": "3.9.1",
-    "gulp-clang-format": "1.0.23",
+    "gulp-clang-format": "^1.0.27",
     "gulp-conventional-changelog": "^2.0.3",
     "gulp-filter": "^5.1.0",
     "gulp-git": "^2.7.0",
diff --git a/tools/gulp-tasks/format.js b/tools/gulp-tasks/format.js
index 90db154597..a9d168f535 100644
--- a/tools/gulp-tasks/format.js
+++ b/tools/gulp-tasks/format.js
@@ -85,7 +85,7 @@ function gulpStatus() {
 }
 
 module.exports = {
-  // Check source code for formatting errors (clang-format)
+  // Check source code for formatting errors with clang-format
   enforce: (gulp) => () => {
     const format = require('gulp-clang-format');
     const clangFormat = require('clang-format');
@@ -93,6 +93,34 @@ module.exports = {
         format.checkFormat('file', clangFormat, {verbose: true, fail: true}));
   },
 
+  // Check only the untracked source code files for formatting errors with .clang-format
+  'enforce-untracked': (gulp) => () => {
+    const format = require('gulp-clang-format');
+    const clangFormat = require('clang-format');
+    const gulpFilter = require('gulp-filter');
+
+    return gulpStatus()
+        .pipe(gulpFilter(srcsToFmt))
+        .pipe(format.checkFormat('file', clangFormat, {verbose: true, fail: true}));
+  },
+
+  // Check only the changed source code files diffed from the provided branch for formatting
+  // errors with clang-format
+  'enforce-diff': (gulp) => () => {
+    const format = require('gulp-clang-format');
+    const clangFormat = require('clang-format');
+    const gulpFilter = require('gulp-filter');
+    const minimist = require('minimist');
+    const gulpGit = require('gulp-git');
+
+    const args = minimist(process.argv.slice(2));
+    const branch = args.branch || 'master';
+
+    return gulpGit.diff(branch, {log: false})
+        .pipe(gulpFilter(srcsToFmt))
+        .pipe(format.checkFormat('file', clangFormat, {verbose: true, fail: true}));
+  },
+
   // Format the source code with clang-format (see .clang-format)
   format: (gulp) => () => {
     const format = require('gulp-clang-format');
diff --git a/yarn.lock b/yarn.lock
index 55922087c0..d7300351b8 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -3570,19 +3570,10 @@ cjson@^0.3.1:
   dependencies:
     json-parse-helpfulerror "^1.0.3"
 
-clang-format@1.0.41:
-  version "1.0.41"
-  resolved "https://registry.yarnpkg.com/clang-format/-/clang-format-1.0.41.tgz#28552e50b0c9e44d23f85aebe3d2fbd06c93620c"
-  integrity sha1-KFUuULDJ5E0j+Frr49L70GyTYgw=
-  dependencies:
-    async "^1.5.2"
-    glob "^7.0.0"
-    resolve "^1.1.6"
-
-clang-format@^1.0.32:
-  version "1.2.3"
-  resolved "https://registry.yarnpkg.com/clang-format/-/clang-format-1.2.3.tgz#2763561aa7449c43737480f8df3a2b5b66e6cf37"
-  integrity sha512-x90Hac4ERacGDcZSvHKK58Ga0STuMD+Doi5g0iG2zf7wlJef5Huvhs/3BvMRFxwRYyYSdl6mpQNrtfMxE8MQzw==
+clang-format@^1.0.32, clang-format@^1.4.0:
+  version "1.4.0"
+  resolved "https://registry.yarnpkg.com/clang-format/-/clang-format-1.4.0.tgz#1ee2f10637eb5bb0bd7d0b82c949af68e848367e"
+  integrity sha512-NrdyUnHJOGvMa60vbWk7GJTvOdhibj3uK5C0FlwdNG4301OUvqEJTFce9I9x8qw2odBbIVrJ+9xbsFS3a4FbDA==
   dependencies:
     async "^1.5.2"
     glob "^7.0.0"
@@ -7020,18 +7011,17 @@ gtoken@^4.1.0:
     jws "^4.0.0"
     mime "^2.2.0"
 
-gulp-clang-format@1.0.23:
-  version "1.0.23"
-  resolved "https://registry.yarnpkg.com/gulp-clang-format/-/gulp-clang-format-1.0.23.tgz#fe258586b83998491e632fc0c4fc0ecdfa10c89f"
-  integrity sha1-/iWFhrg5mEkeYy/AxPwOzfoQyJ8=
+gulp-clang-format@^1.0.27:
+  version "1.0.27"
+  resolved "https://registry.yarnpkg.com/gulp-clang-format/-/gulp-clang-format-1.0.27.tgz#c89716c26745703356c4ff3f2b0964393c73969e"
+  integrity sha512-Jj4PGuNXKdqVCh9fijvL7wdzma5TQRJz1vv8FjOjnSkfq3s/mvbdE/jq+5HG1c/q+jcYkXTEGkYT3CrdnJOLaQ==
   dependencies:
     clang-format "^1.0.32"
+    fancy-log "^1.3.2"
     gulp-diff "^1.0.0"
-    gulp-util "^3.0.4"
-    pkginfo "^0.3.0"
+    plugin-error "^1.0.1"
     stream-combiner2 "^1.1.1"
-    stream-equal "0.1.6"
-    through2 "^0.6.3"
+    through2 "^2.0.3"
 
 gulp-conventional-changelog@^2.0.3:
   version "2.0.3"
@@ -7089,7 +7079,7 @@ gulp-tslint@8.1.2:
     map-stream "~0.0.7"
     through "~2.3.8"
 
-gulp-util@^3.0.0, gulp-util@^3.0.4, gulp-util@^3.0.6, gulp-util@~3.0.8:
+gulp-util@^3.0.0, gulp-util@^3.0.6, gulp-util@~3.0.8:
   version "3.0.8"
   resolved "https://registry.yarnpkg.com/gulp-util/-/gulp-util-3.0.8.tgz#0054e1e744502e27c04c187c3ecc505dd54bbb4f"
   integrity sha1-AFTh50RQLifATBh8PsxQXdVLu08=
@@ -11459,7 +11449,7 @@ pkg-dir@^4.1.0:
   dependencies:
     find-up "^4.0.0"
 
-pkginfo@0.3.x, pkginfo@^0.3.0:
+pkginfo@0.3.x:
   version "0.3.1"
   resolved "https://registry.yarnpkg.com/pkginfo/-/pkginfo-0.3.1.tgz#5b29f6a81f70717142e09e765bbeab97b4f81e21"
   integrity sha1-Wyn2qB9wcXFC4J52W76rl7T4HiE=
@@ -13853,11 +13843,6 @@ stream-each@^1.1.0:
     end-of-stream "^1.1.0"
     stream-shift "^1.0.0"
 
-stream-equal@0.1.6:
-  version "0.1.6"
-  resolved "https://registry.yarnpkg.com/stream-equal/-/stream-equal-0.1.6.tgz#cc522fab38516012e4d4ee47513b147b72359019"
-  integrity sha1-zFIvqzhRYBLk1O5HUTsUe3I1kBk=
-
 stream-http@^2.7.2:
   version "2.8.3"
   resolved "https://registry.yarnpkg.com/stream-http/-/stream-http-2.8.3.tgz#b2d242469288a5a27ec4fe8933acf623de6514fc"
@@ -14445,7 +14430,7 @@ through2@2.0.1:
     readable-stream "~2.0.0"
     xtend "~4.0.0"
 
-through2@^0.6.1, through2@^0.6.3:
+through2@^0.6.1:
   version "0.6.5"
   resolved "https://registry.yarnpkg.com/through2/-/through2-0.6.5.tgz#41ab9c67b29d57209071410e1d7a7a968cd3ad48"
   integrity sha1-QaucZ7KdVyCQcUEOHXp6lozTrUg=