From 6c56a6b33463add8006cdc37141e90474d7afa27 Mon Sep 17 00:00:00 2001
From: Ben Edgington <ben@benjaminion.xyz>
Date: Fri, 10 Mar 2023 09:14:40 +0000
Subject: [PATCH] Add trailing white space check

---
 bin/build/prebuild.js        | 19 +++++++++++++++++++
 bin/build/whitespacecheck.sh | 10 ++++++++++
 2 files changed, 29 insertions(+)
 create mode 100755 bin/build/whitespacecheck.sh

diff --git a/bin/build/prebuild.js b/bin/build/prebuild.js
index 47cc1cc..c79f9aa 100644
--- a/bin/build/prebuild.js
+++ b/bin/build/prebuild.js
@@ -7,6 +7,7 @@ const glob = require('glob')
 //  - Checks that HTML tags are properly balanced
 //  - Spellcheck
 //  - Repeated words check
+//  - Trailing whitespace check
 //  - Lints the source markdown (see lintSourceMarkdown in this file)
 //  - Splits the source markdown into individual pages
 //  - Lints the split markdown (see lintSplitMarkdown in this file)
@@ -15,6 +16,7 @@ const doInternalLinks = true
 const doHtmlCheck = true
 const doSpellCheck = true
 const doRepeatCheck = true
+const doWhitespaceCheck = true
 const doSourceLint = true
 const doSplitLint = true
 
@@ -22,6 +24,7 @@ const linkChecker = 'bin/build/links.pl'
 const htmlChecker = 'bin/build/html.pl'
 const spellChecker = 'bin/build/spellcheck.sh'
 const repeatChecker = 'bin/build/repeatcheck.sh'
+const whitespaceChecker = 'bin/build/whitespacecheck.sh'
 const mdSplitter = 'bin/build/update.sh'
 
 const sourceMarkdown = 'src/book.md'
@@ -105,6 +108,22 @@ module.exports.runChecks = (reporter) => {
     reporter.warn('Skipping repeat check')
   }
 
+  if (doWhitespaceCheck) {
+    reporter.info('Performing trailing whitespace check...')
+    try {
+      const out = execSync(`${whitespaceChecker} ${sourceMarkdown}`, {encoding: 'utf8', stdio: 'pipe'})
+      if (out !== '') {
+        reporter.warn('Found trailing whitespace:')
+        printLines(out, reporter.warn)
+      }
+    } catch (err) {
+      reporter.warn('Unable to perform whitespace check:')
+      printLines(err.toString(), reporter.warn)
+    }
+  } else {
+    reporter.warn('Skipping whitespace check')
+  }
+
   if (doSourceLint) {
     reporter.info('Linting source markdown...')
     try {
diff --git a/bin/build/whitespacecheck.sh b/bin/build/whitespacecheck.sh
new file mode 100755
index 0000000..a34a22b
--- /dev/null
+++ b/bin/build/whitespacecheck.sh
@@ -0,0 +1,10 @@
+#!/bin/bash
+
+# Check the book source, supplied as $1, for trailing whitespace
+
+grep -n '\s$' $1 | awk 'BEGIN {FS=":"} {print "Line " $1}'
+
+# The following allows us to handle the return from grep ("1" is not an error!)
+r=("${PIPESTATUS[@]}")
+(( ${r[0]} )) && (( ${r[0]} != 1 )) && exit ${r[0]}
+exit ${r[1]}