tests: Refactor implementation into separate files

13 files changed, 906 insertions, 823 deletions

diff --git a/tests/bfs/deep_strict.sh b/tests/bfs/deep_strict.sh
index e057310..50c8f05 100644
--- a/tests/bfs/deep_strict.sh
+++ b/tests/bfs/deep_strict.sh
@@ -1,5 +1,3 @@
-closefrom 4
-
 # Not even enough fds to keep the root open
 ulimit -n 7
 bfs_diff deep -type f -exec bash -c 'echo "${1:0:6}/.../${1##*/} (${#1})"' bash {} \;
diff --git a/tests/color.sh b/tests/color.sh
new file mode 100644
index 0000000..0d6ef68
--- /dev/null
+++ b/tests/color.sh
@@ -0,0 +1,43 @@
+#!/hint/bash
+
+# Copyright © Tavian Barnes <tavianator@tavianator.com>
+# SPDX-License-Identifier: 0BSD
+
+## Colored output
+
+# Common escape sequences
+BLD=$'\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 "$1" ]
+}
+
+# Cache the color status for std{out,err}
+color_fd 1 && COLOR_STDOUT=1 || COLOR_STDOUT=0
+color_fd 2 && COLOR_STDERR=1 || COLOR_STDERR=0
+
+# Save these in case the tests unset PATH
+CAT=$(command -v cat)
+SED=$(command -v sed)
+
+# Filter out escape sequences if necessary
+color() {
+    if color_fd 1; then
+        "$CAT"
+    else
+        "$SED" $'s/\e\\[[^m]*m//g'
+    fi
+}
+
+# printf with auto-detected color support
+cprintf() {
+    printf "$@" | color
+}
diff --git a/tests/common/execdir_ulimit.sh b/tests/common/execdir_ulimit.sh
index 8bd9edd..f7fc467 100644
--- a/tests/common/execdir_ulimit.sh
+++ b/tests/common/execdir_ulimit.sh
@@ -2,6 +2,5 @@ clean_scratch
 mkdir -p scratch/a/b/c/d/e/f/g/h/i/j/k/l/m/n/o/p/q/r/s/t/u/v/w/x/y/z
 mkdir -p scratch/a/b/c/d/e/f/g/h/i/j/k/l/m/0/1/2/3/4/5/6/7/8/9/A/B/C
 
-closefrom 4
 ulimit -n 13
 bfs_diff scratch -execdir echo {} \;
diff --git a/tests/getopts.sh b/tests/getopts.sh
new file mode 100644
index 0000000..6616a4a
--- /dev/null
+++ b/tests/getopts.sh
@@ -0,0 +1,158 @@
+#!/hint/bash
+
+# Copyright © Tavian Barnes <tavianator@tavianator.com>
+# SPDX-License-Identifier: 0BSD
+
+## Argument parsing
+
+# Print usage information
+usage() {
+    local pad=$(printf "%*s" ${#0} "")
+    color <<EOF
+Usage: ${GRN}$0${RST} [${BLU}--bfs${RST}=${MAG}path/to/bfs${RST}] [${BLU}--sudo${RST}[=${BLD}COMMAND${RST}]] [${BLU}--stop${RST}]
+       $pad [${BLU}--no-clean${RST}] [${BLU}--update${RST}] [${BLU}--verbose${RST}[=${BLD}LEVEL${RST}]] [${BLU}--help${RST}]
+       $pad [${BLU}--posix${RST}] [${BLU}--bsd${RST}] [${BLU}--gnu${RST}] [${BLU}--all${RST}] [${BLD}TEST${RST} [${BLD}TEST${RST} ...]]
+
+  ${BLU}--bfs${RST}=${MAG}path/to/bfs${RST}
+      Set the path to the bfs executable to test (default: ${MAG}./bin/bfs${RST})
+
+  ${BLU}--sudo${RST}[=${BLD}COMMAND${RST}]
+      Run tests that require root using ${GRN}sudo${RST} or the given ${BLD}COMMAND${RST}
+
+  ${BLU}--stop${RST}
+      Stop when the first error occurs
+
+  ${BLU}--no-clean${RST}
+      Keep the test directories around after the run
+
+  ${BLU}--update${RST}
+      Update the expected outputs for the test cases
+
+  ${BLU}--verbose${RST}=${BLD}commands${RST}
+      Log the commands that get executed
+  ${BLU}--verbose${RST}=${BLD}errors${RST}
+      Don't redirect standard error
+  ${BLU}--verbose${RST}=${BLD}skipped${RST}
+      Log which tests get skipped
+  ${BLU}--verbose${RST}=${BLD}tests${RST}
+      Log all tests that get run
+  ${BLU}--verbose${RST}
+      Log everything
+
+  ${BLU}--help${RST}
+      This message
+
+  ${BLU}--posix${RST}, ${BLU}--bsd${RST}, ${BLU}--gnu${RST}, ${BLU}--all${RST}
+      Choose which test cases to run (default: ${BLU}--all${RST})
+
+  ${BLD}TEST${RST}
+      Select individual test cases to run (e.g. ${BLD}posix/basic${RST}, ${BLD}"*exec*"${RST}, ...)
+EOF
+}
+
+# Parse the command line
+parse_args() {
+    PATTERNS=()
+    SUDO=()
+    STOP=0
+    CLEAN=1
+    UPDATE=0
+    VERBOSE_COMMANDS=0
+    VERBOSE_ERRORS=0
+    VERBOSE_SKIPPED=0
+    VERBOSE_TESTS=0
+
+    for arg; do
+        case "$arg" in
+            --bfs=*)
+                BFS="${arg#*=}"
+                ;;
+            --posix)
+                PATTERNS+=("posix/*")
+                ;;
+            --bsd)
+                PATTERNS+=("posix/*" "common/*" "bsd/*")
+                ;;
+            --gnu)
+                PATTERNS+=("posix/*" "common/*" "gnu/*")
+                ;;
+            --all)
+                PATTERNS+=("*")
+                ;;
+            --sudo)
+                SUDO=(sudo)
+                ;;
+            --sudo=*)
+                read -a SUDO <<<"${arg#*=}"
+                ;;
+            --stop)
+                STOP=1
+                ;;
+            --no-clean|--noclean)
+                CLEAN=0
+                ;;
+            --update)
+                UPDATE=1
+                ;;
+            --verbose=commands)
+                VERBOSE_COMMANDS=1
+                ;;
+            --verbose=errors)
+                VERBOSE_ERRORS=1
+                ;;
+            --verbose=skipped)
+                VERBOSE_SKIPPED=1
+                ;;
+            --verbose=tests)
+                VERBOSE_TESTS=1
+                ;;
+            --verbose)
+                VERBOSE_COMMANDS=1
+                VERBOSE_ERRORS=1
+                VERBOSE_SKIPPED=1
+                VERBOSE_TESTS=1
+                ;;
+            --help)
+                usage
+                exit 0
+                ;;
+            -*)
+                cprintf "${RED}error:${RST} Unrecognized option '%s'.\n\n" "$arg" >&2
+                usage >&2
+                exit 1
+                ;;
+            *)
+                PATTERNS+=("$arg")
+                ;;
+        esac
+    done
+
+    # Try to resolve the path to $BFS before we cd, while also supporting
+    # --bfs="./bin/bfs -S ids"
+    read -a BFS <<<"${BFS:-$BIN/bfs}"
+    BFS[0]=$(_realpath "$(command -v "${BFS[0]}")")
+
+    if ((${#PATTERNS[@]} == 0)); then
+        PATTERNS=("*")
+    fi
+
+    TEST_CASES=()
+    ALL_TESTS=($(cd "$TESTS" && quote {posix,common,bsd,gnu,bfs}/*.sh))
+    for TEST in "${ALL_TESTS[@]}"; do
+        TEST="${TEST%.sh}"
+        for PATTERN in "${PATTERNS[@]}"; do
+            if [[ $TEST == $PATTERN ]]; then
+                TEST_CASES+=("$TEST")
+                break
+            fi
+        done
+    done
+
+    if ((${#TEST_CASES[@]} == 0)); then
+        cprintf "${RED}error:${RST} No tests matched" >&2
+        cprintf " ${BLD}%s${RST}" "${PATTERNS[@]}" >&2
+        cprintf ".\n\n" >&2
+        usage >&2
+        exit 1
+    fi
+}
diff --git a/tests/gnu/printf_u_g_ulimit.sh b/tests/gnu/printf_u_g_ulimit.sh
index a84ee29..390ad48 100644
--- a/tests/gnu/printf_u_g_ulimit.sh
+++ b/tests/gnu/printf_u_g_ulimit.sh
@@ -1,3 +1,2 @@
-closefrom 4
 ulimit -n 16
 [ "$(invoke_bfs deep -printf '%u %g\n' | uniq)" = "$(id -un) $(id -gn)" ]
diff --git a/tests/ls-color.sh b/tests/ls-color.sh
index 9fdd59c..b9a0402 100755
--- a/tests/ls-color.sh
+++ b/tests/ls-color.sh
@@ -7,7 +7,7 @@
 
 set -e
 
-function parse_ls_colors() {
+parse_ls_colors() {
     for key; do
         local -n var="$key"
         if [[ "$LS_COLORS" =~ (^|:)$key=(([^:]|\\:)*) ]]; then
@@ -18,7 +18,7 @@ function parse_ls_colors() {
     done
 }
 
-function re_escape() {
+re_escape() {
     # https://stackoverflow.com/a/29613573/502399
     sed 's/[^^]/[&]/g; s/\^/\\^/g' <<<"$1"
 }
@@ -34,7 +34,7 @@ parse_ls_colors rs lc rc ec no
 
 strip="(($(re_escape "$lc$no$rc"))?($(re_escape "$ec")|$(re_escape "$lc$rc")))+"
 
-function ls_color() {
+ls_color() {
     # Strip the leading reset sequence from the ls output
     ls -1d --color "$@" | sed -E "s/^$strip([a-z].*)$strip/\4/; s/^$strip//"
 }
diff --git a/tests/posix/deep.sh b/tests/posix/deep.sh
index 3d1cd60..431705e 100644
--- a/tests/posix/deep.sh
+++ b/tests/posix/deep.sh
@@ -1,4 +1,2 @@
-closefrom 4
-
 ulimit -n 16
 bfs_diff deep -type f -exec bash -c 'echo "${1:0:6}/.../${1##*/} (${#1})"' bash {} \;
diff --git a/tests/posix/nogroup_ulimit.sh b/tests/posix/nogroup_ulimit.sh
index 8f758c4..2186321 100644
--- a/tests/posix/nogroup_ulimit.sh
+++ b/tests/posix/nogroup_ulimit.sh
@@ -1,4 +1,3 @@
-closefrom 4
 ulimit -n 16
 
 # -mindepth 18, but POSIX
diff --git a/tests/posix/nouser_ulimit.sh b/tests/posix/nouser_ulimit.sh
index 2777589..be0a65f 100644
--- a/tests/posix/nouser_ulimit.sh
+++ b/tests/posix/nouser_ulimit.sh
@@ -1,4 +1,3 @@
-closefrom 4
 ulimit -n 16
 
 # -mindepth 18, but POSIX
diff --git a/tests/run.sh b/tests/run.sh
new file mode 100644
index 0000000..70c9cc2
--- /dev/null
+++ b/tests/run.sh
@@ -0,0 +1,316 @@
+#!/hint/bash
+
+# Copyright © Tavian Barnes <tavianator@tavianator.com>
+# SPDX-License-Identifier: 0BSD
+
+## Running test cases
+
+# Beginning/end of line escape sequences
+BOL=$'\n'
+EOL=$'\n'
+
+# Update $EOL for the terminal size
+update_eol() {
+    # Bash gets $COLUMNS from stderr, so if it's redirected use tput instead
+    local cols="${COLUMNS-}"
+    if [ -z "$cols" ]; then
+        cols=$(tput cols)
+    fi
+
+    # Put the cursor at the last column, then write a space so the next
+    # character will wrap
+    EOL=$'\e['"${cols}G "
+}
+
+# ERR trap for tests
+debug_err() {
+    local ret=$? line func file
+    callers | while read -r line func file; do
+        if [ "$func" = source ]; then
+            local cmd="$(awk "NR == $line" "$file" 2>/dev/null)" || :
+            debug "$file" $line "${RED}error $ret${RST}" "$cmd" >&4
+            break
+        fi
+    done
+}
+
+# Run a single test
+run_test() (
+    set -eE
+    trap debug_err ERR
+    cd "$TMP"
+    source "$@"
+)
+
+# Run all the tests
+run_tests() {
+    if ((VERBOSE_TESTS)); then
+        BOL=''
+    elif ((COLOR_STDOUT)); then
+        # Carriage return + clear line
+        BOL=$'\r\e[K'
+
+        # 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 $COLUMNS
+        shopt -s checkwinsize
+        (:)
+
+        update_eol
+        trap update_eol WINCH
+    fi
+
+    passed=0
+    failed=0
+    skipped=0
+
+    if ((COLOR_STDOUT || VERBOSE_TESTS)); then
+        TEST_FMT="${BOL}${YLW}%s${RST}${EOL}"
+    else
+        TEST_FMT="."
+    fi
+
+    # Turn off set -e (but turn it back on in run_test)
+    set +e
+
+    for TEST in "${TEST_CASES[@]}"; do
+        printf "$TEST_FMT" "$TEST"
+
+        OUT="$TMP/$TEST.out"
+        mkdir -p "${OUT%/*}"
+
+        if ((VERBOSE_ERRORS)); then
+            run_test "$TESTS/$TEST.sh"
+        else
+            run_test "$TESTS/$TEST.sh" 2>"$TMP/$TEST.err"
+        fi
+        status=$?
+
+        if ((status == 0)); then
+            ((++passed))
+        elif ((status == EX_SKIP)); then
+            ((++skipped))
+        else
+            ((++failed))
+            ((VERBOSE_ERRORS)) || cat "$TMP/$TEST.err" >&2
+            cprintf "${BOL}${RED}%s failed!${RST}\n" "$TEST"
+            ((STOP)) && break
+        fi
+    done
+
+    printf "${BOL}"
+
+    if ((passed > 0)); then
+        cprintf "${GRN}tests passed: %d${RST}\n" "$passed"
+    fi
+    if ((skipped > 0)); then
+        cprintf "${CYN}tests skipped: %s${RST}\n" "$skipped"
+    fi
+    if ((failed > 0)); then
+        cprintf "${RED}tests failed: %s${RST}\n" "$failed"
+        exit 1
+    fi
+}
+
+## Utilities for the tests themselves
+
+# Return value when a test is skipped
+EX_SKIP=77
+
+# Skip the current test
+skip() {
+    if ((VERBOSE_SKIPPED)); then
+        caller | {
+            read -r line file
+            printf "${BOL}"
+            debug "$file" $line "${CYN}$TEST skipped!${RST}" "$(awk "NR == $line" "$file")" >&3
+        }
+    elif ((VERBOSE_TESTS)); then
+        cprintf "${BOL}${CYN}%s skipped!${RST}\n" "$TEST"
+    fi
+
+    exit $EX_SKIP
+}
+
+# Run a command and check its exit status
+check_exit() {
+    local expected="$1"
+    local actual="0"
+    shift
+    "$@" || actual="$?"
+    ((actual == expected))
+}
+
+# Run a command with sudo
+bfs_sudo() {
+    if ((${#SUDO[@]})); then
+        "${SUDO[@]}" "$@"
+    else
+        return 1
+    fi
+}
+
+# Get the inode number of a file
+inum() {
+    ls -id "$@" | awk '{ print $1 }'
+}
+
+# Set an ACL on a file
+set_acl() {
+    case "$UNAME" in
+        Darwin)
+            chmod +a "$(id -un) allow read,write" "$1"
+            ;;
+        FreeBSD)
+            if (($(getconf ACL_NFS4 "$1") > 0)); then
+                setfacl -m "u:$(id -un):rw::allow" "$1"
+            else
+                setfacl -m "u:$(id -un):rw" "$1"
+            fi
+            ;;
+        *)
+            setfacl -m "u:$(id -un):rw" "$1"
+            ;;
+    esac
+}
+
+# Print a bfs invocation for --verbose=commands
+bfs_verbose() (
+    if ((!VERBOSE_COMMANDS)); then
+        return
+    fi
+
+    # Free up an fd for the pipe
+    exec 4>&-
+
+    {
+        printf "${GRN}%q${RST} " "${BFS[@]}"
+
+        local expr_started=
+        for arg; do
+            if [[ $arg == -[A-Z]* ]]; then
+                printf "${CYN}%q${RST} " "$arg"
+            elif [[ $arg == [\(!] || $arg == -[ao] || $arg == -and || $arg == -or || $arg == -not ]]; then
+                expr_started=yes
+                printf "${RED}%q${RST} " "$arg"
+            elif [[ $expr_started && $arg == [\),] ]]; then
+                printf "${RED}%q${RST} " "$arg"
+            elif [[ $arg == -?* ]]; then
+                expr_started=yes
+                printf "${BLU}%q${RST} " "$arg"
+            elif [ "$expr_started" ]; then
+                printf "${BLD}%q${RST} " "$arg"
+            else
+                printf "${MAG}%q${RST} " "$arg"
+            fi
+        done
+
+        printf '\n'
+    } | color >&3
+)
+
+# Run the bfs we're testing
+invoke_bfs() {
+    bfs_verbose "$@"
+
+    local ret=0
+    # Close the logging fds
+    "${BFS[@]}" "$@" 3>&- 4>&- || ret=$?
+
+    # Allow bfs to fail, but not crash
+    if ((ret > 125)); then
+        exit "$ret"
+    else
+        return "$ret"
+    fi
+}
+
+if command -v unbuffer &>/dev/null; then
+    UNBUFFER=unbuffer
+elif command -v expect_unbuffer &>/dev/null; then
+    UNBUFFER=expect_unbuffer
+fi
+
+# Run bfs with a pseudo-terminal attached
+bfs_pty() {
+    test -n "${UNBUFFER:-}" || skip
+
+    bfs_verbose "$@"
+
+    local ret=0
+    "$UNBUFFER" bash -c 'stty cols 80 rows 24 && "$@"' bash "${BFS[@]}" "$@" || ret=$?
+
+    if ((ret > 125)); then
+        exit "$ret"
+    else
+        return "$ret"
+    fi
+}
+
+# Create a directory tree with xattrs in scratch
+make_xattrs() {
+    clean_scratch
+
+    "$XTOUCH" scratch/{normal,xattr,xattr_2}
+    ln -s xattr scratch/link
+    ln -s normal scratch/xattr_link
+
+    case "$UNAME" in
+        Darwin)
+            xattr -w bfs_test true scratch/xattr \
+                && xattr -w bfs_test_2 true scratch/xattr_2 \
+                && xattr -s -w bfs_test true scratch/xattr_link
+            ;;
+        FreeBSD)
+            setextattr user bfs_test true scratch/xattr \
+                && setextattr user bfs_test_2 true scratch/xattr_2 \
+                && setextattr -h user bfs_test true scratch/xattr_link
+            ;;
+        *)
+            # Linux tmpfs doesn't support the user.* namespace, so we use the security.*
+            # namespace, which is writable by root and readable by others
+            bfs_sudo setfattr -n security.bfs_test scratch/xattr \
+                && bfs_sudo setfattr -n security.bfs_test_2 scratch/xattr_2 \
+                && bfs_sudo setfattr -h -n security.bfs_test scratch/xattr_link
+            ;;
+    esac
+}
+
+## Snapshot testing
+
+# Return value when a difference is detected
+EX_DIFF=20
+
+# Detect colored diff support
+if ((COLOR_STDERR)) && diff --color=always /dev/null /dev/null 2>/dev/null; then
+    DIFF="diff --color=always"
+else
+    DIFF="diff"
+fi
+
+# Sort the output file
+sort_output() {
+    sort -o "$OUT" "$OUT"
+}
+
+# Diff against the expected output
+diff_output() {
+    local GOLD="$TESTS/$TEST.out"
+
+    if ((UPDATE)); then
+        cp "$OUT" "$GOLD"
+    else
+        $DIFF -u "$GOLD" "$OUT" >&2
+    fi
+}
+
+# Run bfs, and diff it against the expected output
+bfs_diff() {
+    local ret=0
+    invoke_bfs "$@" >"$OUT" || ret=$?
+
+    sort_output
+    diff_output || exit $EX_DIFF
+
+    return $ret
+}
diff --git a/tests/stddirs.sh b/tests/stddirs.sh
new file mode 100644
index 0000000..e7f7246
--- /dev/null
+++ b/tests/stddirs.sh
@@ -0,0 +1,185 @@
+#!/hint/bash
+
+# Copyright © Tavian Barnes <tavianator@tavianator.com>
+# SPDX-License-Identifier: 0BSD
+
+## Standard directory trees for tests
+
+# Creates a simple file+directory structure for tests
+make_basic() {
+    "$XTOUCH" -p "$1"/{a,b,c/d,e/f,g/h/,i/}
+    "$XTOUCH" -p "$1"/{j/foo,k/foo/bar,l/foo/bar/baz}
+    echo baz >"$1/l/foo/bar/baz"
+}
+
+# Creates a file+directory structure with various permissions for tests
+make_perms() {
+    "$XTOUCH" -p -M000 "$1/0"
+    "$XTOUCH" -p -M444 "$1/r"
+    "$XTOUCH" -p -M222 "$1/w"
+    "$XTOUCH" -p -M644 "$1/rw"
+    "$XTOUCH" -p -M555 "$1/rx"
+    "$XTOUCH" -p -M311 "$1/wx"
+    "$XTOUCH" -p -M755 "$1/rwx"
+}
+
+# Creates a file+directory structure with various symbolic and hard links
+make_links() {
+    "$XTOUCH" -p "$1/file"
+    ln -s file "$1/symlink"
+    ln "$1/file" "$1/hardlink"
+    ln -s nowhere "$1/broken"
+    ln -s symlink/file "$1/notdir"
+    "$XTOUCH" -p "$1/deeply/nested"/{dir/,file}
+    ln -s file "$1/deeply/nested/link"
+    ln -s nowhere "$1/deeply/nested/broken"
+    ln -s deeply/nested "$1/skip"
+}
+
+# Creates a file+directory structure with symbolic link loops
+make_loops() {
+    "$XTOUCH" -p "$1/file"
+    ln -s file "$1/symlink"
+    ln -s nowhere "$1/broken"
+    ln -s symlink/file "$1/notdir"
+    ln -s loop "$1/loop"
+    mkdir -p "$1/deeply/nested/dir"
+    ln -s ../../deeply "$1/deeply/nested/loop"
+    ln -s deeply/nested/loop/nested "$1/skip"
+}
+
+# Creates a file+directory structure with varying timestamps
+make_times() {
+    "$XTOUCH" -p -t "1991-12-14 00:00" "$1/a"
+    "$XTOUCH" -p -t "1991-12-14 00:01" "$1/b"
+    "$XTOUCH" -p -t "1991-12-14 00:02" "$1/c"
+    ln -s a "$1/l"
+    "$XTOUCH" -p -h -t "1991-12-14 00:03" "$1/l"
+    "$XTOUCH" -p -t "1991-12-14 00:04" "$1"
+}
+
+# Creates a file+directory structure with various weird file/directory names
+make_weirdnames() {
+    "$XTOUCH" -p "$1/-/a"
+    "$XTOUCH" -p "$1/(/b"
+    "$XTOUCH" -p "$1/(-/c"
+    "$XTOUCH" -p "$1/!/d"
+    "$XTOUCH" -p "$1/!-/e"
+    "$XTOUCH" -p "$1/,/f"
+    "$XTOUCH" -p "$1/)/g"
+    "$XTOUCH" -p "$1/.../h"
+    "$XTOUCH" -p "$1/\\/i"
+    "$XTOUCH" -p "$1/ /j"
+    "$XTOUCH" -p "$1/[/k"
+}
+
+# Creates a very deep directory structure for testing PATH_MAX handling
+make_deep() {
+    mkdir -p "$1"
+
+    # $name will be 255 characters, aka _XOPEN_NAME_MAX
+    local name="0123456789ABCDEF"
+    name="${name}${name}${name}${name}"
+    name="${name}${name}${name}${name}"
+    name="${name:0:255}"
+
+    for i in {0..9} A B C D E F; do
+        "$XTOUCH" -p "$1/$i/$name"
+
+        (
+            cd "$1/$i"
+
+            # 8 * 512 == 4096 >= PATH_MAX
+            for _ in {1..8}; do
+                mv "$name" ..
+                mkdir -p "$name/$name"
+                mv "../$name" "$name/$name/"
+            done
+        )
+    done
+}
+
+# Creates a directory structure with many different types, and therefore colors
+make_rainbow() {
+    "$XTOUCH" -p "$1/file.txt"
+    "$XTOUCH" -p "$1/file.dat"
+    "$XTOUCH" -p "$1/lower".{gz,tar,tar.gz}
+    "$XTOUCH" -p "$1/upper".{GZ,TAR,TAR.GZ}
+    "$XTOUCH" -p "$1/lu.tar.GZ" "$1/ul.TAR.gz"
+    ln -s file.txt "$1/link.txt"
+    "$XTOUCH" -p "$1/mh1"
+    ln "$1/mh1" "$1/mh2"
+    mkfifo "$1/pipe"
+    # TODO: block
+    ln -s /dev/null "$1/chardev_link"
+    ln -s nowhere "$1/broken"
+    "$MKSOCK" "$1/socket"
+    "$XTOUCH" -p "$1"/s{u,g,ug}id
+    chmod u+s "$1"/su{,g}id
+    chmod g+s "$1"/s{u,}gid
+    mkdir "$1/ow" "$1"/sticky{,_ow}
+    chmod o+w "$1"/*ow
+    chmod +t "$1"/sticky*
+    "$XTOUCH" -p "$1"/exec.sh
+    chmod +x "$1"/exec.sh
+    "$XTOUCH" -p "$1/"$'\e[1m/\e[0m'
+}
+
+# Create all standard directory trees
+make_stddirs() {
+    TMP=$(mktemp -d "${TMPDIR:-/tmp}"/bfs.XXXXXXXXXX)
+
+    if ((CLEAN)); then
+        defer clean_stddirs
+    else
+        printf "Test files saved to ${BLD}%s${RST}\n" "$TMP"
+    fi
+
+    chown "$(id -u):$(id -g)" "$TMP"
+
+    make_basic "$TMP/basic"
+    make_perms "$TMP/perms"
+    make_links "$TMP/links"
+    make_loops "$TMP/loops"
+    make_times "$TMP/times"
+    make_weirdnames "$TMP/weirdnames"
+    make_deep "$TMP/deep"
+    make_rainbow "$TMP/rainbow"
+    mkdir "$TMP/scratch"
+}
+
+# Clean whatever was left in the scratch directory
+clean_scratch() {
+    if [ -e "$TMP/scratch" ]; then
+        # Try to unmount anything left behind
+        if ((${#SUDO[@]})) && command -v mountpoint &>/dev/null; then
+            for path in "$TMP/scratch"/*; do
+                if mountpoint -q "$path"; then
+                    sudo umount "$path"
+                fi
+            done
+        fi
+
+        # Reset any modified permissions
+        chmod -R +rX "$TMP/scratch"
+
+        rm -rf "$TMP/scratch"
+    fi
+
+    mkdir "$TMP/scratch"
+}
+
+# Clean up temporary directories on exit
+clean_stddirs() {
+    # Don't force rm to deal with long paths
+    for dir in "$TMP"/deep/*/*; do
+        if [ -d "$dir" ]; then
+            (cd "$dir" && rm -rf *)
+        fi
+    done
+
+    # In case a test left anything weird in scratch/
+    clean_scratch
+
+    rm -rf "$TMP"
+}
diff --git a/tests/tests.sh b/tests/tests.sh
index dcef28e..3890243 100755
--- a/tests/tests.sh
+++ b/tests/tests.sh
@@ -6,815 +6,15 @@
 set -euP
 umask 022
 
-export LC_ALL=C
-export TZ=UTC0
-
-SAN_OPTIONS="halt_on_error=1:log_to_syslog=0"
-export ASAN_OPTIONS="$SAN_OPTIONS"
-export LSAN_OPTIONS="$SAN_OPTIONS"
-export MSAN_OPTIONS="$SAN_OPTIONS"
-export TSAN_OPTIONS="$SAN_OPTIONS"
-export UBSAN_OPTIONS="$SAN_OPTIONS"
-
-export LS_COLORS=""
-unset BFS_COLORS
-
-BLD=$'\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=$'\e[0m'
-
-function color_fd() {
-    [ -z "${NO_COLOR:-}" ] && [ -t "$1" ]
-}
-
-color_fd 1 && COLOR_STDOUT=1 || COLOR_STDOUT=0
-color_fd 2 && COLOR_STDERR=1 || COLOR_STDERR=0
-
-# Filter out escape sequences if necessary
-function color() {
-    if color_fd 1; then
-        cat
-    else
-        sed $'s/\e\\[[^m]*m//g'
-    fi
-}
-
-# printf with auto-detected color support
-function cprintf() {
-    printf "$@" | color
-}
-
-UNAME=$(uname)
-
-if [ "$UNAME" = Darwin ]; then
-    # ASan on macOS likes to report
-    #
-    #     malloc: nano zone abandoned due to inability to preallocate reserved vm space.
-    #
-    # to syslog, which as a side effect opens a socket which might take the
-    # place of one of the standard streams if the process is launched with it
-    # closed.  This environment variable avoids the message.
-    export MallocNanoZone=0
-fi
-
-if command -v capsh &>/dev/null; then
-    if capsh --has-p=cap_dac_override &>/dev/null || capsh --has-p=cap_dac_read_search &>/dev/null; then
-	if [ -n "${BFS_TRIED_DROP:-}" ]; then
-            color >&2 <<EOF
-${RED}error:${RST} Failed to drop capabilities.
-EOF
-
-	    exit 1
-	fi
-
-        color >&2 <<EOF
-${YLW}warning:${RST} Running as ${BLD}$(id -un)${RST} is not recommended.  Dropping ${BLD}cap_dac_override${RST} and
-${BLD}cap_dac_read_search${RST}.
-
-EOF
-
-        BFS_TRIED_DROP=y exec capsh \
-            --drop=cap_dac_override,cap_dac_read_search \
-            --caps=cap_dac_override,cap_dac_read_search-eip \
-            -- "$0" "$@"
-    fi
-elif ((EUID == 0)); then
-    UNLESS=
-    if [ "$UNAME" = "Linux" ]; then
-	UNLESS=" unless ${GRN}capsh${RST} is installed"
-    fi
-
-    color >&2 <<EOF
-${RED}error:${RST} These tests expect filesystem permissions to be enforced, and therefore
-will not work when run as ${BLD}$(id -un)${RST}${UNLESS}.
-EOF
-    exit 1
-fi
-
-function usage() {
-    local pad=$(printf "%*s" ${#0} "")
-    color <<EOF
-Usage: ${GRN}$0${RST} [${BLU}--bfs${RST}=${MAG}path/to/bfs${RST}] [${BLU}--sudo${RST}[=${BLD}COMMAND${RST}]] [${BLU}--stop${RST}]
-       $pad [${BLU}--no-clean${RST}] [${BLU}--update${RST}] [${BLU}--verbose${RST}[=${BLD}LEVEL${RST}]] [${BLU}--help${RST}]
-       $pad [${BLU}--posix${RST}] [${BLU}--bsd${RST}] [${BLU}--gnu${RST}] [${BLU}--all${RST}] [${BLD}TEST${RST} [${BLD}TEST${RST} ...]]
-
-  ${BLU}--bfs${RST}=${MAG}path/to/bfs${RST}
-      Set the path to the bfs executable to test (default: ${MAG}./bin/bfs${RST})
-
-  ${BLU}--sudo${RST}[=${BLD}COMMAND${RST}]
-      Run tests that require root using ${GRN}sudo${RST} or the given ${BLD}COMMAND${RST}
-
-  ${BLU}--stop${RST}
-      Stop when the first error occurs
-
-  ${BLU}--no-clean${RST}
-      Keep the test directories around after the run
-
-  ${BLU}--update${RST}
-      Update the expected outputs for the test cases
-
-  ${BLU}--verbose${RST}=${BLD}commands${RST}
-      Log the commands that get executed
-  ${BLU}--verbose${RST}=${BLD}errors${RST}
-      Don't redirect standard error
-  ${BLU}--verbose${RST}=${BLD}skipped${RST}
-      Log which tests get skipped
-  ${BLU}--verbose${RST}=${BLD}tests${RST}
-      Log all tests that get run
-  ${BLU}--verbose${RST}
-      Log everything
-
-  ${BLU}--help${RST}
-      This message
-
-  ${BLU}--posix${RST}, ${BLU}--bsd${RST}, ${BLU}--gnu${RST}, ${BLU}--all${RST}
-      Choose which test cases to run (default: ${BLU}--all${RST})
-
-  ${BLD}TEST${RST}
-      Select individual test cases to run (e.g. ${BLD}posix/basic${RST}, ${BLD}"*exec*"${RST}, ...)
-EOF
-}
-
-PATTERNS=()
-SUDO=()
-STOP=0
-CLEAN=1
-UPDATE=0
-VERBOSE_COMMANDS=0
-VERBOSE_ERRORS=0
-VERBOSE_SKIPPED=0
-VERBOSE_TESTS=0
-
-for arg; do
-    case "$arg" in
-        --bfs=*)
-            BFS="${arg#*=}"
-            ;;
-        --posix)
-            PATTERNS+=("posix/*")
-            ;;
-        --bsd)
-            PATTERNS+=("posix/*" "common/*" "bsd/*")
-            ;;
-        --gnu)
-            PATTERNS+=("posix/*" "common/*" "gnu/*")
-            ;;
-        --all)
-            PATTERNS+=("*")
-            ;;
-        --sudo)
-            SUDO=(sudo)
-            ;;
-        --sudo=*)
-            read -a SUDO <<<"${arg#*=}"
-            ;;
-        --stop)
-            STOP=1
-            ;;
-        --no-clean|--noclean)
-            CLEAN=0
-            ;;
-        --update)
-            UPDATE=1
-            ;;
-        --verbose=commands)
-            VERBOSE_COMMANDS=1
-            ;;
-        --verbose=errors)
-            VERBOSE_ERRORS=1
-            ;;
-        --verbose=skipped)
-            VERBOSE_SKIPPED=1
-            ;;
-        --verbose=tests)
-            VERBOSE_TESTS=1
-            ;;
-        --verbose)
-            VERBOSE_COMMANDS=1
-            VERBOSE_ERRORS=1
-            VERBOSE_SKIPPED=1
-            VERBOSE_TESTS=1
-            ;;
-        --help)
-            usage
-            exit 0
-            ;;
-        -*)
-            cprintf "${RED}error:${RST} Unrecognized option '%s'.\n\n" "$arg" >&2
-            usage >&2
-            exit 1
-            ;;
-        *)
-            PATTERNS+=("$arg")
-            ;;
-    esac
-done
-
-function _realpath() {
-    (
-        cd "$(dirname -- "$1")"
-        echo "$PWD/$(basename -- "$1")"
-    )
-}
-
-TESTS=$(_realpath "$(dirname -- "${BASH_SOURCE[0]}")")
-
-if [ "${BUILDDIR-}" ]; then
-    BIN=$(_realpath "$BUILDDIR/bin")
-else
-    BIN=$(_realpath "$TESTS/../bin")
-fi
-MKSOCK="$BIN/tests/mksock"
-XTOUCH="$BIN/tests/xtouch"
-
-# Try to resolve the path to $BFS before we cd, while also supporting
-# --bfs="./bin/bfs -S ids"
-read -a BFS <<<"${BFS:-$BIN/bfs}"
-BFS[0]=$(_realpath "$(command -v "${BFS[0]}")")
-
-# The temporary directory that will hold our test data
-TMP=$(mktemp -d "${TMPDIR:-/tmp}"/bfs.XXXXXXXXXX)
-chown "$(id -u):$(id -g)" "$TMP"
-
-cd "$TESTS"
-
-if ((${#PATTERNS[@]} == 0)); then
-    PATTERNS=("*")
-fi
-
-TEST_CASES=()
-for TEST in {posix,common,bsd,gnu,bfs}/*.sh; do
-    TEST="${TEST%.sh}"
-    for PATTERN in "${PATTERNS[@]}"; do
-        if [[ $TEST == $PATTERN ]]; then
-            TEST_CASES+=("$TEST")
-            break
-        fi
-    done
-done
-
-if ((${#TEST_CASES[@]} == 0)); then
-    cprintf "${RED}error:${RST} No tests matched" >&2
-    cprintf " ${BLD}%s${RST}" "${PATTERNS[@]}" >&2
-    cprintf ".\n\n" >&2
-    usage >&2
-    exit 1
-fi
-
-function quote() {
-    printf '%q' "$1"
-    shift
-    if (($# > 0)); then
-        printf ' %q' "$@"
-    fi
-}
-
-# Run a command when this (sub)shell exits
-function defer() {
-    trap -- KILL
-    if ! trap -p EXIT | grep -q pop_defers; then
-        DEFER_CMDS=()
-        DEFER_LINES=()
-        DEFER_FILES=()
-        trap pop_defers EXIT
-    fi
-
-    DEFER_CMDS+=("$(quote "$@")")
-
-    local line file
-    read -r line file < <(caller)
-    DEFER_LINES+=("$line")
-    DEFER_FILES+=("$file")
-}
-
-function report_err() {
-    local file="${1/#*\/tests\//tests\/}"
-    set -- "$file" "${@:2}"
-
-    if ((COLOR_STDERR)); then
-        printf "${BLD}%s:%d:${RST} ${RED}error %d:${RST}\n    %s\n" "$@" >&2
-    else
-        printf "%s:%d: error %d:\n    %s\n" "$@" >&2
-    fi
-}
-
-function pop_defer() {
-    local cmd="${DEFER_CMDS[-1]}"
-    local file="${DEFER_FILES[-1]}"
-    local line="${DEFER_LINES[-1]}"
-    unset "DEFER_CMDS[-1]"
-    unset "DEFER_FILES[-1]"
-    unset "DEFER_LINES[-1]"
-
-    local ret=0
-    eval "$cmd" || ret=$?
-
-    if ((ret != 0)); then
-        report_err "$file" $line $ret "defer $cmd"
-    fi
-
-    return $ret
-}
-
-function pop_defers() {
-    local ret=0
-
-    while ((${#DEFER_CMDS[@]} > 0)); do
-        pop_defer || ret=$?
-    done
-
-    return $ret
-}
-
-function bfs_sudo() {
-    if ((${#SUDO[@]})); then
-        "${SUDO[@]}" "$@"
-    else
-        return 1
-    fi
-}
-
-function clean_scratch() {
-    if [ -e "$TMP/scratch" ]; then
-        # Try to unmount anything left behind
-        if ((${#SUDO[@]})) && command -v mountpoint &>/dev/null; then
-            for path in "$TMP"/scratch/*; do
-                if mountpoint -q "$path"; then
-                    sudo umount "$path"
-                fi
-            done
-        fi
-
-        # Reset any modified permissions
-        chmod -R +rX "$TMP/scratch"
-
-        rm -rf "$TMP/scratch"
-    fi
-
-    mkdir "$TMP/scratch"
-}
-
-# Clean up temporary directories on exit
-function cleanup() {
-    # Don't force rm to deal with long paths
-    for dir in "$TMP"/deep/*/*; do
-        if [ -d "$dir" ]; then
-            (cd "$dir" && rm -rf *)
-        fi
-    done
-
-    # In case a test left anything weird in scratch/
-    clean_scratch
-
-    rm -rf "$TMP"
-}
-
-if ((CLEAN)); then
-    defer cleanup
-else
-    echo "Test files saved to $TMP"
-fi
-
-# Creates a simple file+directory structure for tests
-function make_basic() {
-    "$XTOUCH" -p "$1"/{a,b,c/d,e/f,g/h/,i/}
-    "$XTOUCH" -p "$1"/{j/foo,k/foo/bar,l/foo/bar/baz}
-    echo baz >"$1/l/foo/bar/baz"
-}
-make_basic "$TMP/basic"
-
-# Creates a file+directory structure with various permissions for tests
-function make_perms() {
-    "$XTOUCH" -p -M000 "$1/0"
-    "$XTOUCH" -p -M444 "$1/r"
-    "$XTOUCH" -p -M222 "$1/w"
-    "$XTOUCH" -p -M644 "$1/rw"
-    "$XTOUCH" -p -M555 "$1/rx"
-    "$XTOUCH" -p -M311 "$1/wx"
-    "$XTOUCH" -p -M755 "$1/rwx"
-}
-make_perms "$TMP/perms"
-
-# Creates a file+directory structure with various symbolic and hard links
-function make_links() {
-    "$XTOUCH" -p "$1/file"
-    ln -s file "$1/symlink"
-    ln "$1/file" "$1/hardlink"
-    ln -s nowhere "$1/broken"
-    ln -s symlink/file "$1/notdir"
-    "$XTOUCH" -p "$1/deeply/nested"/{dir/,file}
-    ln -s file "$1/deeply/nested/link"
-    ln -s nowhere "$1/deeply/nested/broken"
-    ln -s deeply/nested "$1/skip"
-}
-make_links "$TMP/links"
-
-# Creates a file+directory structure with symbolic link loops
-function make_loops() {
-    "$XTOUCH" -p "$1/file"
-    ln -s file "$1/symlink"
-    ln -s nowhere "$1/broken"
-    ln -s symlink/file "$1/notdir"
-    ln -s loop "$1/loop"
-    mkdir -p "$1/deeply/nested/dir"
-    ln -s ../../deeply "$1/deeply/nested/loop"
-    ln -s deeply/nested/loop/nested "$1/skip"
-}
-make_loops "$TMP/loops"
-
-# Creates a file+directory structure with varying timestamps
-function make_times() {
-    "$XTOUCH" -p -t "1991-12-14 00:00" "$1/a"
-    "$XTOUCH" -p -t "1991-12-14 00:01" "$1/b"
-    "$XTOUCH" -p -t "1991-12-14 00:02" "$1/c"
-    ln -s a "$1/l"
-    "$XTOUCH" -p -h -t "1991-12-14 00:03" "$1/l"
-    "$XTOUCH" -p -t "1991-12-14 00:04" "$1"
-}
-make_times "$TMP/times"
-
-# Creates a file+directory structure with various weird file/directory names
-function make_weirdnames() {
-    "$XTOUCH" -p "$1/-/a"
-    "$XTOUCH" -p "$1/(/b"
-    "$XTOUCH" -p "$1/(-/c"
-    "$XTOUCH" -p "$1/!/d"
-    "$XTOUCH" -p "$1/!-/e"
-    "$XTOUCH" -p "$1/,/f"
-    "$XTOUCH" -p "$1/)/g"
-    "$XTOUCH" -p "$1/.../h"
-    "$XTOUCH" -p "$1/\\/i"
-    "$XTOUCH" -p "$1/ /j"
-    "$XTOUCH" -p "$1/[/k"
-}
-make_weirdnames "$TMP/weirdnames"
-
-# Creates a very deep directory structure for testing PATH_MAX handling
-function make_deep() {
-    mkdir -p "$1"
-
-    # $name will be 255 characters, aka _XOPEN_NAME_MAX
-    local name="0123456789ABCDEF"
-    name="${name}${name}${name}${name}"
-    name="${name}${name}${name}${name}"
-    name="${name:0:255}"
-
-    for i in {0..9} A B C D E F; do
-        "$XTOUCH" -p "$1/$i/$name"
-
-        (
-            cd "$1/$i"
-
-            # 8 * 512 == 4096 >= PATH_MAX
-            for _ in {1..8}; do
-                mv "$name" ..
-                mkdir -p "$name/$name"
-                mv "../$name" "$name/$name/"
-            done
-        )
-    done
-}
-make_deep "$TMP/deep"
-
-# Creates a directory structure with many different types, and therefore colors
-function make_rainbow() {
-    "$XTOUCH" -p "$1/file.txt"
-    "$XTOUCH" -p "$1/file.dat"
-    "$XTOUCH" -p "$1/lower".{gz,tar,tar.gz}
-    "$XTOUCH" -p "$1/upper".{GZ,TAR,TAR.GZ}
-    "$XTOUCH" -p "$1/lu.tar.GZ" "$1/ul.TAR.gz"
-    ln -s file.txt "$1/link.txt"
-    "$XTOUCH" -p "$1/mh1"
-    ln "$1/mh1" "$1/mh2"
-    mkfifo "$1/pipe"
-    # TODO: block
-    ln -s /dev/null "$1/chardev_link"
-    ln -s nowhere "$1/broken"
-    "$MKSOCK" "$1/socket"
-    "$XTOUCH" -p "$1"/s{u,g,ug}id
-    chmod u+s "$1"/su{,g}id
-    chmod g+s "$1"/s{u,}gid
-    mkdir "$1/ow" "$1"/sticky{,_ow}
-    chmod o+w "$1"/*ow
-    chmod +t "$1"/sticky*
-    "$XTOUCH" -p "$1"/exec.sh
-    chmod +x "$1"/exec.sh
-    "$XTOUCH" -p "$1/"$'\e[1m/\e[0m'
-}
-make_rainbow "$TMP/rainbow"
-
-mkdir "$TMP/scratch"
-
-# Close stdin so bfs doesn't think we're interactive
-exec </dev/null
-
-if ((VERBOSE_COMMANDS)); then
-    # dup stdout for verbose logging even when redirected
-    exec 3>&1
-fi
-
-function bfs_verbose() {
-    if ((!VERBOSE_COMMANDS)); then
-        return
-    fi
-
-    {
-        printf "${GRN}%q${RST} " "${BFS[@]}"
-
-        local expr_started=
-        for arg; do
-            if [[ $arg == -[A-Z]* ]]; then
-                printf "${CYN}%q${RST} " "$arg"
-            elif [[ $arg == [\(!] || $arg == -[ao] || $arg == -and || $arg == -or || $arg == -not ]]; then
-                expr_started=yes
-                printf "${RED}%q${RST} " "$arg"
-            elif [[ $expr_started && $arg == [\),] ]]; then
-                printf "${RED}%q${RST} " "$arg"
-            elif [[ $arg == -?* ]]; then
-                expr_started=yes
-                printf "${BLU}%q${RST} " "$arg"
-            elif [ "$expr_started" ]; then
-                printf "${BLD}%q${RST} " "$arg"
-            else
-                printf "${MAG}%q${RST} " "$arg"
-            fi
-        done
-
-        printf '\n'
-    } | color >&3
-}
-
-function invoke_bfs() {
-    bfs_verbose "$@"
-
-    local ret=0
-    "${BFS[@]}" "$@" || ret=$?
-
-    # Allow bfs to fail, but not crash
-    if ((ret > 125)); then
-        exit "$ret"
-    else
-        return "$ret"
-    fi
-}
-
-if command -v unbuffer &>/dev/null; then
-    UNBUFFER=unbuffer
-elif command -v expect_unbuffer &>/dev/null; then
-    UNBUFFER=expect_unbuffer
-fi
-
-function bfs_pty() {
-    test -n "${UNBUFFER:-}" || skip
-
-    bfs_verbose "$@"
-
-    local ret=0
-    "$UNBUFFER" bash -c 'stty cols 80 rows 24 && "$@"' bash "${BFS[@]}" "$@" || ret=$?
-
-    if ((ret > 125)); then
-        exit "$ret"
-    else
-        return "$ret"
-    fi
-}
-
-function check_exit() {
-    local expected="$1"
-    local actual="0"
-    shift
-    "$@" || actual="$?"
-    ((actual == expected))
-}
-
-# Detect colored diff support
-if ((COLOR_STDERR)) && diff --color=always /dev/null /dev/null 2>/dev/null; then
-    DIFF="diff --color=always"
-else
-    DIFF="diff"
-fi
-
-# Return value when a difference is detected
-EX_DIFF=20
-# Return value when a test is skipped
-EX_SKIP=77
-
-function sort_output() {
-    sort -o "$OUT" "$OUT"
-}
-
-function diff_output() {
-    local GOLD="$TESTS/$TEST.out"
-
-    if ((UPDATE)); then
-        cp "$OUT" "$GOLD"
-    else
-        $DIFF -u "$GOLD" "$OUT" >&2
-    fi
-}
-
-function bfs_diff() (
-    bfs_verbose "$@"
-
-    # Close the dup()'d stdout to make sure we have enough fd's for the process
-    # substitution, even with low ulimit -n
-    exec 3>&-
-
-    "${BFS[@]}" "$@" | sort >"$OUT"
-    local status="${PIPESTATUS[0]}"
-
-    diff_output || exit $EX_DIFF
-    return "$status"
-)
-
-function skip() {
-    if ((VERBOSE_SKIPPED)); then
-        caller | {
-            read -r line file
-            cprintf "${BOL}${CYN}%s skipped!${RST} (%s)\n" "$TEST" "$(awk "NR == $line" "$file")"
-        }
-    elif ((VERBOSE_TESTS)); then
-        cprintf "${BOL}${CYN}%s skipped!${RST}\n" "$TEST"
-    fi
-
-    exit $EX_SKIP
-}
-
-function closefrom() {
-    if [ -d /proc/self/fd ]; then
-        local fds=/proc/self/fd
-    else
-        local fds=/dev/fd
-    fi
-
-    for fd in "$fds"/*; do
-        if [ ! -e "$fd" ]; then
-            continue
-        fi
-
-        local fd="${fd##*/}"
-        if ((fd >= $1)); then
-            eval "exec ${fd}<&-"
-        fi
-    done
-}
-
-function inum() {
-    ls -id "$@" | awk '{ print $1 }'
-}
-
-function set_acl() {
-    case "$UNAME" in
-        Darwin)
-            chmod +a "$(id -un) allow read,write" "$1"
-            ;;
-        FreeBSD)
-            if (($(getconf ACL_NFS4 "$1") > 0)); then
-                setfacl -m "u:$(id -un):rw::allow" "$1"
-            else
-                setfacl -m "u:$(id -un):rw" "$1"
-            fi
-            ;;
-        *)
-            setfacl -m "u:$(id -un):rw" "$1"
-            ;;
-    esac
-}
-
-function make_xattrs() {
-    clean_scratch
-
-    "$XTOUCH" scratch/{normal,xattr,xattr_2}
-    ln -s xattr scratch/link
-    ln -s normal scratch/xattr_link
-
-    case "$UNAME" in
-        Darwin)
-            xattr -w bfs_test true scratch/xattr \
-                && xattr -w bfs_test_2 true scratch/xattr_2 \
-                && xattr -s -w bfs_test true scratch/xattr_link
-            ;;
-        FreeBSD)
-            setextattr user bfs_test true scratch/xattr \
-                && setextattr user bfs_test_2 true scratch/xattr_2 \
-                && setextattr -h user bfs_test true scratch/xattr_link
-            ;;
-        *)
-            # Linux tmpfs doesn't support the user.* namespace, so we use the security.*
-            # namespace, which is writable by root and readable by others
-            bfs_sudo setfattr -n security.bfs_test scratch/xattr \
-                && bfs_sudo setfattr -n security.bfs_test_2 scratch/xattr_2 \
-                && bfs_sudo setfattr -h -n security.bfs_test scratch/xattr_link
-            ;;
-    esac
-}
-
-cd "$TMP"
-set +e
-
-BOL='\n'
-EOL='\n'
-
-function update_eol() {
-    # Bash gets $COLUMNS from stderr, so if it's redirected use tput instead
-    local cols="${COLUMNS-}"
-    if [ -z "$cols" ]; then
-        cols=$(tput cols)
-    fi
-
-    # Put the cursor at the last column, then write a space so the next
-    # character will wrap
-    EOL="\\033[${cols}G "
-}
-
-if ((VERBOSE_TESTS)); then
-    BOL=''
-elif ((COLOR_STDOUT)); then
-    BOL='\r\033[K'
-
-    # 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 $COLUMNS
-    shopt -s checkwinsize
-    (:)
-
-    update_eol
-    trap update_eol WINCH
-fi
-
-function callers() {
-    local frame=0
-    while caller $frame; do
-        ((++frame))
-    done
-}
-
-function debug_err() {
-    local ret=$? line func file
-    callers | while read -r line func file; do
-        if [ "$func" = source ]; then
-            local cmd="$(awk "NR == $line" "$file" 2>/dev/null)" || :
-            report_err "$file" $line $ret "$cmd"
-            break
-        fi
-    done
-}
-
-function run_test() (
-    set -eE
-    trap debug_err ERR
-    source "$@"
-)
-
-passed=0
-failed=0
-skipped=0
-
-if ((COLOR_STDOUT || VERBOSE_TESTS)); then
-    TEST_FMT="${BOL}${YLW}%s${RST}${EOL}"
-else
-    TEST_FMT="."
-fi
-
-for TEST in "${TEST_CASES[@]}"; do
-    printf "$TEST_FMT" "$TEST"
-
-    OUT="$TMP/$TEST.out"
-    mkdir -p "${OUT%/*}"
-
-    if ((VERBOSE_ERRORS)); then
-        run_test "$TESTS/$TEST.sh"
-    else
-        run_test "$TESTS/$TEST.sh" 2>"$TMP/$TEST.err"
-    fi
-    status=$?
-
-    if ((status == 0)); then
-        ((++passed))
-    elif ((status == EX_SKIP)); then
-        ((++skipped))
-    else
-        ((++failed))
-        ((VERBOSE_ERRORS)) || cat "$TMP/$TEST.err" >&2
-        cprintf "${BOL}${RED}%s failed!${RST}\n" "$TEST"
-        ((STOP)) && break
-    fi
-done
-
-printf "${BOL}"
-
-if ((passed > 0)); then
-    cprintf "${GRN}tests passed: %d${RST}\n" "$passed"
-fi
-if ((skipped > 0)); then
-    cprintf "${CYN}tests skipped: %s${RST}\n" "$skipped"
-fi
-if ((failed > 0)); then
-    cprintf "${RED}tests failed: %s${RST}\n" "$failed"
-    exit 1
-fi
+TESTS="$(dirname -- "${BASH_SOURCE[0]}")"
+. "$TESTS/util.sh"
+. "$TESTS/color.sh"
+. "$TESTS/stddirs.sh"
+. "$TESTS/getopts.sh"
+. "$TESTS/run.sh"
+
+stdenv
+drop_root "$@"
+parse_args "$@"
+make_stddirs
+run_tests
diff --git a/tests/util.sh b/tests/util.sh
new file mode 100644
index 0000000..5131522
--- /dev/null
+++ b/tests/util.sh
@@ -0,0 +1,189 @@
+#!/hint/bash
+
+# Copyright © Tavian Barnes <tavianator@tavianator.com>
+# SPDX-License-Identifier: 0BSD
+
+## Utility functions
+
+# Portable realpath(1)
+_realpath() (
+    cd "$(dirname -- "$1")"
+    echo "$PWD/$(basename -- "$1")"
+)
+
+# Globals
+TESTS=$(_realpath "$TESTS")
+if [ "${BUILDDIR-}" ]; then
+    BIN=$(_realpath "$BUILDDIR/bin")
+else
+    BIN=$(_realpath "$TESTS/../bin")
+fi
+MKSOCK="$BIN/tests/mksock"
+XTOUCH="$BIN/tests/xtouch"
+UNAME=$(uname)
+
+# Standardize the environment
+stdenv() {
+    export LC_ALL=C
+    export TZ=UTC0
+
+    local SAN_OPTIONS="halt_on_error=1:log_to_syslog=0"
+    export ASAN_OPTIONS="$SAN_OPTIONS"
+    export LSAN_OPTIONS="$SAN_OPTIONS"
+    export MSAN_OPTIONS="$SAN_OPTIONS"
+    export TSAN_OPTIONS="$SAN_OPTIONS"
+    export UBSAN_OPTIONS="$SAN_OPTIONS"
+
+    export LS_COLORS=""
+    unset BFS_COLORS
+
+    if [ "$UNAME" = Darwin ]; then
+        # ASan on macOS likes to report
+        #
+        #     malloc: nano zone abandoned due to inability to preallocate reserved vm space.
+        #
+        # to syslog, which as a side effect opens a socket which might take the
+        # place of one of the standard streams if the process is launched with
+        # it closed.  This environment variable avoids the message.
+        export MallocNanoZone=0
+    fi
+
+    # Close non-standard inherited fds
+    if [ -d /proc/self/fd ]; then
+        local fds=/proc/self/fd
+    else
+        local fds=/dev/fd
+    fi
+
+    for fd in "$fds"/*; do
+        if [ ! -e "$fd" ]; then
+            continue
+        fi
+
+        local fd="${fd##*/}"
+        if ((fd > 2)); then
+            eval "exec ${fd}<&-"
+        fi
+    done
+
+    # Close stdin so bfs doesn't think we're interactive
+    # dup() the standard fds for logging even when redirected
+    exec </dev/null 3>&1 4>&2
+}
+
+# Drop root priviliges or bail
+drop_root() {
+    if command -v capsh &>/dev/null; then
+        if capsh --has-p=cap_dac_override &>/dev/null || capsh --has-p=cap_dac_read_search &>/dev/null; then
+	    if [ -n "${BFS_TRIED_DROP:-}" ]; then
+                color >&2 <<EOF
+${RED}error:${RST} Failed to drop capabilities.
+EOF
+
+	        exit 1
+	    fi
+
+            color >&2 <<EOF
+${YLW}warning:${RST} Running as ${BLD}$(id -un)${RST} is not recommended.  Dropping ${BLD}cap_dac_override${RST} and
+${BLD}cap_dac_read_search${RST}.
+
+EOF
+
+            BFS_TRIED_DROP=y exec capsh \
+                --drop=cap_dac_override,cap_dac_read_search \
+                --caps=cap_dac_override,cap_dac_read_search-eip \
+                -- "$0" "$@"
+        fi
+    elif ((EUID == 0)); then
+        UNLESS=
+        if [ "$UNAME" = "Linux" ]; then
+	    UNLESS=" unless ${GRN}capsh${RST} is installed"
+        fi
+
+        color >&2 <<EOF
+${RED}error:${RST} These tests expect filesystem permissions to be enforced, and therefore
+will not work when run as ${BLD}$(id -un)${RST}${UNLESS}.
+EOF
+        exit 1
+    fi
+}
+
+## Debugging
+
+# Get the bash call stack
+callers() {
+    local frame=0
+    while caller $frame; do
+        ((++frame))
+    done
+}
+
+# Print a message including path, line number, and command
+debug() {
+    local file="${1/#*\/tests\//tests\/}"
+    set -- "$file" "${@:2}"
+    cprintf "${BLD}%s:%d:${RST} %s\n    %s\n" "$@"
+}
+
+## Deferred cleanup
+
+# Quote a command safely for eval
+quote() {
+    printf '%q' "$1"
+    shift
+    if (($# > 0)); then
+        printf ' %q' "$@"
+    fi
+}
+
+# Run a command when this (sub)shell exits
+defer() {
+    # Refresh trap state before trap -p
+    # See https://unix.stackexchange.com/a/556888/56202
+    trap -- KILL
+
+    # Check if the EXIT trap is already set
+    if ! trap -p EXIT | grep -q pop_defers; then
+        DEFER_CMDS=()
+        DEFER_LINES=()
+        DEFER_FILES=()
+        trap pop_defers EXIT
+    fi
+
+    DEFER_CMDS+=("$(quote "$@")")
+
+    local line file
+    read -r line file < <(caller)
+    DEFER_LINES+=("$line")
+    DEFER_FILES+=("$file")
+}
+
+# Pop a single command from the defer stack and run it
+pop_defer() {
+    local cmd="${DEFER_CMDS[-1]}"
+    local file="${DEFER_FILES[-1]}"
+    local line="${DEFER_LINES[-1]}"
+    unset "DEFER_CMDS[-1]"
+    unset "DEFER_FILES[-1]"
+    unset "DEFER_LINES[-1]"
+
+    local ret=0
+    eval "$cmd" || ret=$?
+
+    if ((ret != 0)); then
+        debug "$file" $line "${RED}error $ret${RST}" "defer $cmd" >&4
+    fi
+
+    return $ret
+}
+
+# Run all deferred commands
+pop_defers() {
+    local ret=0
+
+    while ((${#DEFER_CMDS[@]} > 0)); do
+        pop_defer || ret=$?
+    done
+
+    return $ret
+}