CI: Visibly print trailing whitespace when static checks fail

GitHub Actions seems to be hiding colored whitespace, and after lots of
attempts I couldn't find a way to work it around.

So instead I'm using a perl expression to replace trailing spaces with
`·` and tabs with `<TAB>` in the ANSI colored diff output. This ensure
that they're visible, and they are properly colored as expected too.

(cherry picked from commit 266280ffca218ae1c86e6d83d9b67a16086148b8)

6 files changed, 37 insertions, 28 deletions

diff --git a/misc/scripts/black_format.sh b/misc/scripts/black_format.sh
index f6fac58e50..3a64284eb6 100755
--- a/misc/scripts/black_format.sh
+++ b/misc/scripts/black_format.sh
@@ -13,13 +13,14 @@ diff=$(git diff --color)
 
 # If no diff has been generated all is OK, clean up, and exit.
 if [ -z "$diff" ] ; then
-    printf "Files in this commit comply with the black style rules.\n"
+    printf "\e[1;32m*** Files in this commit comply with the black style rules.\e[0m\n"
     exit 0
 fi
 
 # A diff has been created, notify the user, clean up, and exit.
-printf "\n*** The following differences were found between the code "
-printf "and the formatting rules:\n\n"
-echo "$diff"
-printf "\n*** Aborting, please fix your commit(s) with 'git commit --amend' or 'git rebase -i <hash>'\n"
+printf "\n\e[1;33m*** The following changes must be made to comply with the formatting rules:\e[0m\n\n"
+# Perl commands replace trailing spaces with `·` and tabs with `<TAB>`.
+printf "$diff\n" | perl -pe 's/(.*[^ ])( +)(\e\[m)$/my $spaces="·" x length($2); sprintf("$1$spaces$3")/ge' | perl -pe 's/(.*[^\t])(\t+)(\e\[m)$/my $tabs="<TAB>" x length($2); sprintf("$1$tabs$3")/ge'
+
+printf "\n\e[1;91m*** Please fix your commit(s) with 'git commit --amend' or 'git rebase -i <hash>'\e[0m\n"
 exit 1
diff --git a/misc/scripts/clang_format.sh b/misc/scripts/clang_format.sh
index edecdb6ecb..318a78b865 100755
--- a/misc/scripts/clang_format.sh
+++ b/misc/scripts/clang_format.sh
@@ -33,12 +33,14 @@ diff=$(git diff --color)
 
 # If no diff has been generated all is OK, clean up, and exit.
 if [ -z "$diff" ] ; then
-    printf "Files in this commit comply with the clang-format style rules.\n"
+    printf "\e[1;32m*** Files in this commit comply with the clang-format style rules.\e[0m\n"
     exit 0
 fi
 
 # A diff has been created, notify the user, clean up, and exit.
-printf "\n*** The following changes have been made to comply with the formatting rules:\n\n"
-echo "$diff"
-printf "\n*** Please fix your commit(s) with 'git commit --amend' or 'git rebase -i <hash>'\n"
+printf "\n\e[1;33m*** The following changes must be made to comply with the formatting rules:\e[0m\n\n"
+# Perl commands replace trailing spaces with `·` and tabs with `<TAB>`.
+printf "$diff\n" | perl -pe 's/(.*[^ ])( +)(\e\[m)$/my $spaces="·" x length($2); sprintf("$1$spaces$3")/ge' | perl -pe 's/(.*[^\t])(\t+)(\e\[m)$/my $tabs="<TAB>" x length($2); sprintf("$1$tabs$3")/ge'
+
+printf "\n\e[1;91m*** Please fix your commit(s) with 'git commit --amend' or 'git rebase -i <hash>'\e[0m\n"
 exit 1
diff --git a/misc/scripts/clang_tidy.sh b/misc/scripts/clang_tidy.sh
index 63c1b10042..c4811b903c 100755
--- a/misc/scripts/clang_tidy.sh
+++ b/misc/scripts/clang_tidy.sh
@@ -20,12 +20,14 @@ diff=$(git diff --color)
 
 # If no diff has been generated all is OK, clean up, and exit.
 if [ -z "$diff" ] ; then
-    printf "Files in this commit comply with the clang-tidy style rules.\n"
+    printf "\e[1;32m*** Files in this commit comply with the clang-tidy style rules.\e[0m\n"
     exit 0
 fi
 
 # A diff has been created, notify the user, clean up, and exit.
-printf "\n*** The following changes have been made to comply with the formatting rules:\n\n"
-echo "$diff"
-printf "\n*** Please fix your commit(s) with 'git commit --amend' or 'git rebase -i <hash>'\n"
+printf "\n\e[1;33m*** The following changes must be made to comply with the formatting rules:\e[0m\n\n"
+# Perl commands replace trailing spaces with `·` and tabs with `<TAB>`.
+printf "$diff\n" | perl -pe 's/(.*[^ ])( +)(\e\[m)$/my $spaces="·" x length($2); sprintf("$1$spaces$3")/ge' | perl -pe 's/(.*[^\t])(\t+)(\e\[m)$/my $tabs="<TAB>" x length($2); sprintf("$1$tabs$3")/ge'
+
+printf "\n\e[1;91m*** Please fix your commit(s) with 'git commit --amend' or 'git rebase -i <hash>'\e[0m\n"
 exit 1
diff --git a/misc/scripts/dotnet_format.sh b/misc/scripts/dotnet_format.sh
index cc34137a37..cac00f5cb1 100755
--- a/misc/scripts/dotnet_format.sh
+++ b/misc/scripts/dotnet_format.sh
@@ -24,12 +24,14 @@ diff=$(git diff --color)
 
 # If no diff has been generated all is OK, clean up, and exit.
 if [ -z "$diff" ] ; then
-    printf "Files in this commit comply with the dotnet format style rules.\n"
+    printf "\e[1;32m*** Files in this commit comply with the dotnet format style rules.\e[0m\n"
     exit 0
 fi
 
 # A diff has been created, notify the user, clean up, and exit.
-printf "\n*** The following changes have been made to comply with the formatting rules:\n\n"
-echo "$diff"
-printf "\n*** Please fix your commit(s) with 'git commit --amend' or 'git rebase -i <hash>'\n"
+printf "\n\e[1;33m*** The following changes must be made to comply with the formatting rules:\e[0m\n\n"
+# Perl commands replace trailing spaces with `·` and tabs with `<TAB>`.
+printf "$diff\n" | perl -pe 's/(.*[^ ])( +)(\e\[m)$/my $spaces="·" x length($2); sprintf("$1$spaces$3")/ge' | perl -pe 's/(.*[^\t])(\t+)(\e\[m)$/my $tabs="<TAB>" x length($2); sprintf("$1$tabs$3")/ge'
+
+printf "\n\e[1;91m*** Please fix your commit(s) with 'git commit --amend' or 'git rebase -i <hash>'\e[0m\n"
 exit 1
diff --git a/misc/scripts/file_format.sh b/misc/scripts/file_format.sh
index 3ff5798e22..f394c4ad3f 100755
--- a/misc/scripts/file_format.sh
+++ b/misc/scripts/file_format.sh
@@ -56,7 +56,7 @@ diff=$(git diff --color)
 if [ ! -s utf8-validation.txt ] && [ -z "$diff" ] ; then
     # If no UTF-8 violations were collected (the file is empty) and
     # no diff has been generated all is OK, clean up, and exit.
-    printf "Files in this commit comply with the formatting rules.\n"
+    printf "\e[1;32m*** Files in this commit comply with the file formatting rules.\e[0m\n"
     rm -f utf8-validation.txt
     exit 0
 fi
@@ -65,7 +65,7 @@ if [ -s utf8-validation.txt ]
 then
     # If the file has content and is not empty, violations
     # detected, notify the user, clean up, and exit.
-    printf "\n*** The following files contain invalid UTF-8 character sequences:\n\n"
+    printf "\n\e[1;33m*** The following files contain invalid UTF-8 character sequences:\e[0m\n\n"
     cat utf8-validation.txt
 fi
 
@@ -73,10 +73,11 @@ rm -f utf8-validation.txt
 
 if [ ! -z "$diff" ]
 then
-    printf "\n*** The following differences were found between the code "
-    printf "and the formatting rules:\n\n"
-    echo "$diff"
+    # A diff has been created, notify the user, clean up, and exit.
+    printf "\n\e[1;33m*** The following changes must be made to comply with the formatting rules:\e[0m\n\n"
+    # Perl commands replace trailing spaces with `·` and tabs with `<TAB>`.
+    printf "$diff\n" | perl -pe 's/(.*[^ ])( +)(\e\[m)$/my $spaces="·" x length($2); sprintf("$1$spaces$3")/ge' | perl -pe 's/(.*[^\t])(\t+)(\e\[m)$/my $tabs="<TAB>" x length($2); sprintf("$1$tabs$3")/ge'
 fi
 
-printf "\n*** Aborting, please fix your commit(s) with 'git commit --amend' or 'git rebase -i <hash>'\n"
+printf "\n\e[1;91m*** Please fix your commit(s) with 'git commit --amend' or 'git rebase -i <hash>'\e[0m\n"
 exit 1
diff --git a/misc/scripts/header_guards.sh b/misc/scripts/header_guards.sh
index 9fdc864f8c..a063ff4b9c 100755
--- a/misc/scripts/header_guards.sh
+++ b/misc/scripts/header_guards.sh
@@ -66,13 +66,14 @@ diff=$(git diff --color)
 
 # If no diff has been generated all is OK, clean up, and exit.
 if [ -z "$diff" ] ; then
-    printf "Files in this commit comply with the header guards formatting rules.\n"
+    printf "\e[1;32m*** Files in this commit comply with the header guards formatting rules.\e[0m\n"
     exit 0
 fi
 
 # A diff has been created, notify the user, clean up, and exit.
-printf "\n*** The following differences were found between the code "
-printf "and the header guards formatting rules:\n\n"
-echo "$diff"
-printf "\n*** Aborting, please fix your commit(s) with 'git commit --amend' or 'git rebase -i <hash>'\n"
+printf "\n\e[1;33m*** The following changes must be made to comply with the formatting rules:\e[0m\n\n"
+# Perl commands replace trailing spaces with `·` and tabs with `<TAB>`.
+printf "$diff\n" | perl -pe 's/(.*[^ ])( +)(\e\[m)$/my $spaces="·" x length($2); sprintf("$1$spaces$3")/ge' | perl -pe 's/(.*[^\t])(\t+)(\e\[m)$/my $tabs="<TAB>" x length($2); sprintf("$1$tabs$3")/ge'
+
+printf "\n\e[1;91m*** Please fix your commit(s) with 'git commit --amend' or 'git rebase -i <hash>'\e[0m\n"
 exit 1