linter

#!/bin/bash

# Helper functions

function print_lined_uncorrectable_issue {
	((uncorrectable_issues+=1))
	local text="Uncorrectable issue: $1 at '$2' in line $3 in '$4'."
	output+=$'\n'"$text"
}
function print_file_uncorrectable_issue {
	((uncorrectable_issues+=1))
	local text="Uncorrectable issue: $1 in file '$2'"
	output+=$'\n'"$text"
}

function print_lined_correctable_issue {
	((correctable_issues+=1))
	local text="Correctable issue: $1 at '$2' in line $3 in '$4'."
	output+=$'\n'"$text"
}
function print_file_correctable_issue {
	((correctable_issues+=1))
	local text="Correctable issue: $1 in file '$2'"
	output+=$'\n'"$text"
}

function print_welcome {
	echo "Issues marked as uncorrectable are not fixable by the auto-linter"
	echo "Issues marked as correctable are probably fixable by the auto-linter"
}

# Linting Functions

function lint_st {
	if [[ $1 =~ "monticello.meta/initializers.st" ]]; then
		return
	fi

	# echo . used to preserve trailing newlines
	local content="$(cat "$1"; echo .)"
	content="${content%.}"

	if (echo -n "$content" | grep "This is an auto-generated method" > /dev/null); then
		return
	fi

	local line_number=1
	while IFS= read -r line
	do
		[[ $line =~ ^.{81,1000}$ ]] && print_lined_uncorrectable_issue "Line too long" "$line" "$line_number" "$1"
		[[ $line =~ ([^[:space:]]@)|(@[^[:space:]]) ]] && print_lined_correctable_issue "No spaces around '@'" "$line" "$line_number" "$1"
		[[ $line =~ ([aA])([[:space:]]?M2) ]] && print_lined_correctable_issue "Usage of 'aM2', 'a M2', 'A M2' or 'AM2'" "$line" "$line_number" "$1"
		[[ $line =~ ([[:space:]])\) ]] && print_lined_correctable_issue "No spaces around brackets" "$line" "$line_number" "$1"
		[[ $line =~ \(([[:space:]]) ]] && print_lined_correctable_issue "No spaces around brackets" "$line" "$line_number" "$1"
		[[ $line =~ [^[:space:]][[:space:]]$ ]] && print_lined_correctable_issue "Trailing space" "$line" "$line_number" "$1"
		((line_number+=1))
	done <<< "$content"
	[[ $content =~ ^([^[]+?)([[:space:]]{3,})(\|) ]] && print_file_correctable_issue "Empty lines before method local variables" "$1"
	[[ $content =~ ^([^[]+?)(\|)([[:space:]]{3,}) ]] && print_file_correctable_issue "Empty lines before method local variables" "$1"
	[[ $content =~ (\.)([[:space:]]*)$ ]] && print_file_correctable_issue "Final point" "$1"
	# bash doesn't support lookarounds in regexes, use grep with -z (effectively treats input as one line) instead
	(echo -n "$content" | grep -zP '\S\n(?![\s\S])' >/dev/null) || print_file_correctable_issue "More or less than one trailing newline" "$1"
}

function lint_md {
	local content=$(<"$1")
	local line_number=1
	while IFS= read -r line
	do
		[[ $line =~ ([aA])([[:space:]]?M2) ]] && print_lined_correctable_issue "Usage of 'aM2', 'a M2', 'A M2' or 'AM2'" "$line" "$line_number" "$1"
		((line_number+=1))
	done <<< "$content"
	[[ $content =~ ^[[:space:]]*$ ]] && print_file_uncorrectable_issue "Empty class comment" "$1"
}

# Main script

print_welcome

uncorrectable_issues=0
correctable_issues=0

output=""

echo "Linting..."

while IFS= read -rd '' f
do
	lint_st "$f"
done < <(git ls-files '*.st' -z)

while IFS= read -rd '' f
do
	lint_md "$f"
done < <(git ls-files '*.md' -z)

total_issues=0
((total_issues+=uncorrectable_issues))
((total_issues+=correctable_issues))

if (( total_issues == 0 ))
then
	echo "No issues found."
	exit 0
else
	echo "Linting results:"
	echo "$output"

	echo "Uncorrectable issues: $uncorrectable_issues; correctable issues: $correctable_issues"
	exit 0 # Temporarily un-fail until there is a way to ignore certain rules on lines
fi