From ecfb7c6a7faa3a7b321738cadda1194c70744879 Mon Sep 17 00:00:00 2001
From: Anders Kaseorg <anders@zulipchat.com>
Date: Sat, 20 Jul 2019 11:40:36 -0700
Subject: [PATCH] lint: Add TypeScript compiler as a linter.

Signed-off-by: Anders Kaseorg <anders@zulipchat.com>
---
 docs/testing/linters.md    |  2 ++
 docs/testing/typescript.md | 10 +++++-----
 package.json               |  1 +
 static/js/tsconfig.json    |  1 +
 tools/lint                 |  2 ++
 tools/run-tsc              |  3 +++
 version.py                 |  2 +-
 yarn.lock                  |  5 +++++
 8 files changed, 20 insertions(+), 6 deletions(-)
 create mode 100755 tools/run-tsc

diff --git a/docs/testing/linters.md b/docs/testing/linters.md
index 2a63e83fcb..a6a84ea465 100644
--- a/docs/testing/linters.md
+++ b/docs/testing/linters.md
@@ -106,6 +106,8 @@ following checks:
 - Running `mypy` to check static types in Python code.  Our
   [documentation on using mypy](../testing/mypy.html) covers mypy in
   more detail.
+- Running `tsc` to compile TypeScript code.  Our [documentation on
+  TypeScript](typescript.html) covers TypeScript in more detail.
 
 The rest of this document pertains to the checks that occur in `./tools/lint`.
 
diff --git a/docs/testing/typescript.md b/docs/testing/typescript.md
index 09d1f88f0c..385d65235a 100644
--- a/docs/testing/typescript.md
+++ b/docs/testing/typescript.md
@@ -32,11 +32,11 @@ The following resources are valuable for learning TypeScript:
 
 ## Type checking
 
-TypeScript types are checked primarily via `webpack`, so you'll see
-typing errors in red in your `run-dev.py` console as you do
-development.
-
-TODO: Document command for running the type check manually.
+TypeScript types are checked by the TypeScript compiler, `tsc`, which
+is run as part of our [lint checks](linters.html).  You can run the
+compiler yourself with `tools/run-tsc`, which will check all the
+TypeScript files once, or `tools/run-tsc --watch`, which will
+continually recheck the files as you edit them.
 
 ## Linting and style
 
diff --git a/package.json b/package.json
index 6287ce2c86..5b755d50ff 100644
--- a/package.json
+++ b/package.json
@@ -60,6 +60,7 @@
     "zxcvbn": "4.4.2"
   },
   "devDependencies": {
+    "@types/source-map": "0.5.2",
     "@typescript-eslint/eslint-plugin": "^1.12.0",
     "@typescript-eslint/parser": "^1.12.0",
     "casperjs": "casperjs/casperjs",
diff --git a/static/js/tsconfig.json b/static/js/tsconfig.json
index 442398e616..cd5984b36d 100644
--- a/static/js/tsconfig.json
+++ b/static/js/tsconfig.json
@@ -7,6 +7,7 @@
         // "incremental": true,
 
         /* Basic options */
+        "noEmit": true,
         "target": "es5",
         "module": "es6",
         "jsx": "preserve",
diff --git a/tools/lint b/tools/lint
index a88c480e0a..e212e8bc58 100755
--- a/tools/lint
+++ b/tools/lint
@@ -84,6 +84,8 @@ def run():
         command.append('--force')
     linter_config.external_linter('mypy', command, ['py'], pass_targets=False,
                                   description="Static type checker for Python (config: mypy.ini)")
+    linter_config.external_linter('tsc', ['tools/run-tsc'], ['ts'], pass_targets=False,
+                                  description="TypeScript compiler (config: static/js/tsconfig.json)")
     linter_config.external_linter('gitlint', ['tools/commit-message-lint'],
                                   description="Checks commit messages for common formatting errors."
                                   "(config: .gitlint)")
diff --git a/tools/run-tsc b/tools/run-tsc
new file mode 100755
index 0000000000..d6bb801345
--- /dev/null
+++ b/tools/run-tsc
@@ -0,0 +1,3 @@
+#!/bin/sh
+ZULIP_PATH="$(dirname "$0")/.."
+exec "$ZULIP_PATH/node_modules/.bin/tsc" --project "$ZULIP_PATH/static/js" "$@"
diff --git a/version.py b/version.py
index 2212d6eeaf..8afbb7c350 100644
--- a/version.py
+++ b/version.py
@@ -26,4 +26,4 @@ LATEST_RELEASE_ANNOUNCEMENT = "https://blog.zulip.org/2019/03/01/zulip-2-0-relea
 #   historical commits sharing the same major version, in which case a
 #   minor version bump suffices.
 
-PROVISION_VERSION = '42.0'
+PROVISION_VERSION = '42.1'
diff --git a/yarn.lock b/yarn.lock
index 085bc8936f..d6c485902a 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -329,6 +329,11 @@
     "@types/express-serve-static-core" "*"
     "@types/mime" "*"
 
+"@types/source-map@0.5.2":
+  version "0.5.2"
+  resolved "https://registry.yarnpkg.com/@types/source-map/-/source-map-0.5.2.tgz#973459e744cc7445c85b97f770275b479b138e08"
+  integrity sha512-++w4WmMbk3dS3UeHGzAG+xJOSz5Xqtjys/TBkqG3qp3SeWE7Wwezqe5eB7B51cxUyh4PW7bwVotpsLdBK0D8cw==
+
 "@types/tapable@*":
   version "1.0.4"
   resolved "https://registry.yarnpkg.com/@types/tapable/-/tapable-1.0.4.tgz#b4ffc7dc97b498c969b360a41eee247f82616370"