Add checks for whitespace consistency (#405)

* Add checks for whitespace consistency

* Fix name of check_whitespace job

* Fix paths

.circleci/config.yml

@@ -1,5 +1,16 @@
 version: 2.1
 jobs:
+  check_whitespace:
+    docker:
+      - image: cimg/base:2020.01
+    steps:
+      - checkout
+      - run:
+          name: Check for trailing whitespace
+          command: ./dev-scripts/check-trailing-whitespace
+      - run:
+          name: Check that all text files end in a trailing newline
+          command: ./dev-scripts/check-trailing-newline
   build_python:
     docker:
       - image: circleci/python:3.7.3
@@ -37,6 +48,7 @@ jobs:
 workflows:
   test:
     jobs:
+      - check_whitespace
       - build_python
       - format_frontend
       - e2e

.dependabot/config.yml

@@ -7,4 +7,4 @@ update_configs:
       - match:
           # We need to use a specific pylint version that's compatible with
           # DocStringChecker.
-          dependency_name: "pylint"
+          dependency_name: "pylint"

app/views.py

@@ -18,4 +18,4 @@ def index_get():
 def stream_get():
     if flask.current_app.debug:
         return flask.send_file('tests/data/test-remote-screen.jpg')
-    return flask.abort(404)
+    return flask.abort(404)

dev-scripts/build

@@ -9,5 +9,7 @@ set -x
 # Exit on unset variable.
 set -u
 
+./dev-scripts/check-trailing-whitespace
+./dev-scripts/check-trailing-newline
 ./dev-scripts/build-python
-./dev-scripts/check-frontend-format
+./dev-scripts/check-frontend-format

dev-scripts/check-frontend-format

@@ -9,4 +9,4 @@ set -x
 # Exit on unset variable.
 set -u
 
-./node_modules/.bin/prettier --check app/static
+./node_modules/.bin/prettier --check app/static

dev-scripts/check-trailing-newline

@@ -0,0 +1,33 @@
+#!/bin/bash
+
+# Verify that all text files end in a trailing newline.
+
+# Exit on first failing command.
+set -e
+# Exit on unset variable.
+set -u
+
+FILES=$(find . \
+  -type f \
+  -not -path "./.git/*" \
+  -not -path "./venv/*" \
+  -not -path "./node_modules/*" \
+  -not -path "*/third_party/*" \
+  -not -path "*/third-party/*" \
+  -not -path "*.svg" \
+  -exec grep \
+  --binary-files=without-match \
+  --quiet \
+  . {} \; -print)
+
+SUCCESS=0
+
+for F in ${FILES[*]}
+do
+  if ! [[ -s "$F" && -z "$(tail -c 1 "$F")" ]]; then
+    printf "File must end in a trailing newline: $F\n"
+    SUCCESS=-1
+  fi
+done
+
+exit "$SUCCESS"

dev-scripts/check-trailing-whitespace

@@ -0,0 +1,21 @@
+#!/bin/bash
+
+# Check for trailing whitespace
+
+# Echo commands to console.
+set -x
+# Exit on first failing command.
+set -e
+# Exit on unset variable.
+set -u
+
+if egrep \
+  "\s$" \
+  --line-number \
+  --binary-files=without-match \
+  --dereference-recursive \
+  --exclude-dir={.git,venv,node_modules} \
+  ./ ; then
+  echo "ERROR: Found trailing whitespace";
+  exit 1;
+fi

hooks/enable_hooks

@@ -17,4 +17,4 @@ then
   rm -rf .git/hooks
 fi
 
-ln -s -f ../hooks .git/hooks
+ln -s -f ../hooks .git/hooks

hooks/pre-commit

@@ -9,4 +9,4 @@ set -x
 # Exit on unset variable.
 set -u
 
-./dev-scripts/build
+./dev-scripts/build