echo-math: don't use awk, it is too fragile, use deno as bc fallback …

…instead

/ref https://github.com/bevry/dorothy/actions/runs/10876782442/job/30177194414#step:2:2920

commands/echo-math

@@ -5,26 +5,43 @@ function echo_math_test() (
 	echo-style --h1="TEST: $0"
 
 	local inputs=('1 - 1/2' '1 - 1/3' '1 - 1/4')
-	local expected=$'0.50\n0.67\n0.75'
+	local expected_six=$'0.500000\n0.666667\n0.750000'
+	local expected_two=$'0.50\n0.67\n0.75'
 
 	if command-exists -- bc; then
-		eval-tester --stdout="$expected" \
+		eval-tester --stdout="$expected_six" \
+			-- echo-math --tool=bc -- "${inputs[@]}"
+
+		{
+			__print_lines "${inputs[@]}"
+		} | eval-tester --stdout="$expected_six" \
+			-- echo-math --tool=bc --stdin
+
+		eval-tester --stdout="$expected_two" \
 			-- echo-math --precision=2 --tool=bc -- "${inputs[@]}"
 
 		{
 			__print_lines "${inputs[@]}"
-		} | eval-tester --stdout="$expected" \
+		} | eval-tester --stdout="$expected_two" \
 			-- echo-math --precision=2 --tool=bc --stdin
 	fi
 
-	if command-exists -- awk; then
-		eval-tester --stdout="$expected" \
-			-- echo-math --precision=2 --tool=awk -- "${inputs[@]}"
+	if command-exists -- deno; then
+		eval-tester --stdout="$expected_six" \
+			-- echo-math --tool=deno -- "${inputs[@]}"
 
 		{
 			__print_lines "${inputs[@]}"
-		} | eval-tester --stdout="$expected" \
-			-- echo-math --precision=2 --tool=awk --stdin
+		} | eval-tester --stdout="$expected_six" \
+			-- echo-math --tool=deno --stdin
+
+		eval-tester --stdout="$expected_two" \
+			-- echo-math --precision=2 --tool=deno -- "${inputs[@]}"
+
+		{
+			__print_lines "${inputs[@]}"
+		} | eval-tester --stdout="$expected_two" \
+			-- echo-math --precision=2 --tool=deno --stdin
 	fi
 
 	echo-style --g1="TEST: $0"
@@ -48,11 +65,11 @@ function echo_math() (
 			OPTIONS:
 			--precision=<precision>
 			    The number of decimals to round to.
-			    Defaults to [6] which is the default for [awk] for consistency.
+			    Defaults to [6].
 
 			--tool=<tool>
 			    The math engine to use.
-			    Defaults to [bc] if available, otherwise [awk] if available, otherwise failure.
+			    Defaults to [bc] if available, otherwise [deno] if available, otherwise failure.
 
 			$(stdinargs_options_help --)
 		EOF
@@ -77,39 +94,39 @@ function echo_math() (
 			shift $#
 			break
 			;;
-		'--'*) option_args+=("$item") ;;
+		*) option_args+=("$item") ;;
 		esac
 	done
 
 	if test -z "$option_tool"; then
 		if command-exists -- bc; then
 			option_tool='bc'
-		elif command-exists -- gawk; then
-			option_tool='gawk'
-		elif command-exists -- awk; then
-			option_tool='awk'
+		elif command-exists -- deno; then
+			option_tool='deno'
 		fi
 	elif ! command-exists -- "$option_tool"; then
 		help "Missing math <tool>: $option_tool"
 	fi
 
-	# =====================================
-	# Dependencies
-
 	# =====================================
 	# Action
 
+	# bc: 0 decimals by default
+	# bc -l: 20 decimals by default
+	# 0. becomes ., hence need for printf
+	# awk: 6 decimals by default
+
 	if test "$option_tool" = 'bc'; then
 		function on_line {
-			# bc: 0 decimals by default, bc -l: 20 decimals by default
-			# 0. becomes ., hence need for printf
-			printf "%.${option_precision}f\n" "$(bc -l <<<"$1")"
+			local formula="$1"
+			printf "%.${option_precision}f\n" "$(bc -l <<<"$formula")"
 		}
-	elif test "$option_tool" = 'awk' -o "$option_tool" = 'gawk'; then
-		local awk_script
-		awk_script="$(type -P echo-math.awk)"
+	elif test "$option_tool" = 'deno'; then
+		local deno_script
+		deno_script="$(type -P echo-math.ts)"
 		function on_line {
-			"$option_tool" -v option_precision="$option_precision" -v option_number="$1" -f "$awk_script"
+			local formula="$1"
+			"$deno_script" "$option_precision" "$formula"
 		}
 	else
 		help 'No math engine found.'

commands/echo-math.ts

@@ -0,0 +1,6 @@
+#!/usr/bin/env -S deno run --quiet --no-config --no-lock --no-npm --no-remote --cached-only
+const precision = Number(Deno.args[0])
+const formula = Deno.args[1]
+const result = Number(eval(formula))
+const output = result.toFixed(precision)
+console.log(output)