1 files changed, 151 insertions, 0 deletions
diff --git a/tests/color.sh b/tests/color.sh
new file mode 100644
index 0000000..9e2e0f6
--- /dev/null
+++ b/tests/color.sh
@@ -0,0 +1,151 @@
+#!/hint/bash
+
+# Copyright © Tavian Barnes <tavianator@tavianator.com>
+# SPDX-License-Identifier: 0BSD
+
+## Colored output
+
+# Common escape sequences
+BLD=$'\e[01m'
+RED=$'\e[01;31m'
+GRN=$'\e[01;32m'
+YLW=$'\e[01;33m'
+BLU=$'\e[01;34m'
+MAG=$'\e[01;35m'
+CYN=$'\e[01;36m'
+RST=$'\e[0m'
+
+# Check if we should color output to the given fd
+color_fd() {
+    [ -z "${NO_COLOR:-}" ] && [ -t "$1" ]
+}
+
+# Cache the color status for std{out,err}
+color_fd 1 && COLOR_STDOUT=1 || COLOR_STDOUT=0
+color_fd 2 && COLOR_STDERR=1 || COLOR_STDERR=0
+
+# Save this in case the tests unset PATH
+SED=$(command -v sed)
+
+# Filter out escape sequences if necessary
+color() {
+    if color_fd 1; then
+        "$@"
+    else
+        "$@" | "$SED" $'s/\e\\[[^m]*m//g'
+    fi
+}
+
+## Status bar
+
+# Show the terminal status bar
+show_bar() {
+    if [ -z "$TTY" ]; then
+        return 1
+    fi
+
+    # Name the pipe deterministically based on the ttyname, so that concurrent
+    # tests.sh runs on the same terminal (e.g. make -jN check) cooperate
+    local pipe="${TMPDIR:-/tmp}/bfs${TTY//\//-}.bar"
+
+    if mkfifo "$pipe" 2>/dev/null; then
+        # We won the race, create the background process to manage the bar
+        bar_proc "$pipe" &
+        exec {BAR}>"$pipe"
+    elif [ -p "$pipe" ]; then
+        # We lost the race, connect to the existing process.
+        # There is a small TOCTTOU race here but I don't see how to avoid it.
+        exec {BAR}>"$pipe"
+    else
+        return 1
+    fi
+}
+
+# Print to the terminal status bar
+print_bar() {
+    printf 'PRINT:%d:%s\0' $$ "$1" >&$BAR
+}
+
+# Hide the terminal status bar
+hide_bar() {
+    printf 'HIDE:%d:\0' $$ >&$BAR
+    exec {BAR}>&-
+    unset BAR
+}
+
+# The background process that muxes multiple status bars for one TTY
+bar_proc() {
+    # Read from the pipe, write to the TTY
+    exec <"$1" >/dev/tty
+
+    # Delete the pipe when done
+    defer rm "$1"
+    # Reset the scroll region when done
+    defer printf '\e7\e[r\e8\e[J'
+
+    # Workaround for bash 4: checkwinsize is off by default.  We can turn it
+    # on, but we also have to explicitly trigger a foreground job to finish
+    # so that it will update the window size before we use $LINES
+    shopt -s checkwinsize
+    (:)
+
+    BAR_HEIGHT=0
+    resize_bar
+    # Adjust the bar when the TTY size changes
+    trap resize_bar WINCH
+
+    # Map from PID to status bar
+    local -A pid2bar
+
+    # Read commands of the form "OP:PID:STRING\0"
+    while IFS=':' read -r -d '' op pid str; do
+        # Map the pid to a bar, creating a new one if necessary
+        if [ -z "${pid2bar[$pid]:-}" ]; then
+            pid2bar["$pid"]=$((BAR_HEIGHT++))
+            resize_bar
+        fi
+        bar="${pid2bar[$pid]}"
+
+        case "$op" in
+            PRINT)
+                printf '\e7\e[%d;0f\e[K%s\e8' $((TTY_HEIGHT - bar)) "$str"
+                ;;
+            HIDE)
+                bar="${pid2bar[$pid]}"
+                # Delete this status bar
+                unset 'pid2bar[$pid]'
+                # Shift all higher status bars down
+                for i in "${!pid2bar[@]}"; do
+                    ibar="${pid2bar[$i]}"
+                    if ((ibar > bar)); then
+                        pid2bar["$i"]=$((ibar - 1))
+                    fi
+                done
+                ((BAR_HEIGHT--))
+                resize_bar
+                ;;
+        esac
+    done
+}
+
+# Resize the status bar
+resize_bar() {
+    # Bash gets $LINES from stderr, so if it's redirected use tput instead
+    TTY_HEIGHT="${LINES:-$(tput lines 2>/dev/tty)}"
+
+    if ((BAR_HEIGHT == 0)); then
+        return
+    fi
+
+    # Hide the bars temporarily
+    local seq='\e7\e[r\e8\e[J'
+    # Print \eD (IND) N times to ensure N blank lines at the bottom
+    for ((i = 0; i < BAR_HEIGHT; ++i)); do
+        seq="${seq}\\eD"
+    done
+    # Go back up N lines
+    seq="${seq}\\e[${BAR_HEIGHT}A"
+    # Create the new scroll region
+    seq="${seq}\\e7\\e[;$((TTY_HEIGHT - BAR_HEIGHT))r\\e8\\e[J"
+    printf "$seq"
+}