realign-spaces: align lines composed of fields separated by blankspaces

README.md

@@ -80,6 +80,7 @@ This repository hosts various small personal tools.
 - [`r2w_plugins`](r2w_plugins): 2 rest2web plugins
 - [`radiodump`](radiodump): circular buffer and dump to file
 - [`random-line`](random-line): take a random line from stdin
+- [`realign-spaces`](realign-spaces): align lines composed of fields separated by blankspaces
 - [`realign-text-table`](realign-text-table): takes a malformed ASCII-drawn table and redraw borders properly
 - [`gitlab-delete-your-comments.py`](redacting/gitlab-delete-your-comments.py): delete your own gitlab comments on issues/MRs/etc.
 - [`matrix-redact-room.py`](redacting/matrix-redact-room.py): redact messages in a Matrix room of all users or a specific user (resumable)

realign-spaces/realign-spaces.py

@@ -0,0 +1,74 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: WTFPL
+
+import argparse
+import locale
+import os
+from pathlib import Path
+import signal
+import sys
+import shlex
+import shutil
+import tempfile
+
+__version__ = "0.1.0"
+
+
+def process(args, splitfunc, quotefunc):
+    data = []
+    width = []
+    for line in args.file:
+        data.append([quotefunc(part) for part in splitfunc(line)])
+
+        linewidth = [len(part) for part in data[-1]]
+        width.extend([0] * (len(data[-1]) - len(width)))
+        for n, partwidth in enumerate(linewidth):
+            width[n] = max(width[n], partwidth)
+
+    outfile = sys.stdout
+    if args.inplace:
+        outfile = tempfile.NamedTemporaryFile("w+", encoding="utf8", dir=Path(args.file.name).parent)
+
+    for lineparts in data:
+        line = " ".join(f"{part:{width[n]}s}" for n, part in enumerate(lineparts))
+        line = line.strip()
+        print(line, file=outfile)
+
+    if args.inplace:
+        # we want to copy permissions etc. but still mark file as modified now
+        shutil.copystat(args.file.name, outfile.name)
+        os.utime(outfile.name)
+        os.replace(outfile.name, args.file.name)
+
+
+def main():
+    locale.setlocale(locale.LC_ALL, "")
+
+    signal.signal(signal.SIGINT, signal.SIG_DFL)
+    signal.signal(signal.SIGPIPE, signal.SIG_DFL)
+
+    parser = argparse.ArgumentParser()
+    parser.add_argument(
+        "file", type=argparse.FileType(mode="r"), nargs="?", default=sys.stdin,
+    )
+    parser.add_argument("--version", action="version", version=__version__)
+    parser.add_argument(
+        "--shell-split", action="store_true",
+    )
+    parser.add_argument(
+        "-i", "--inplace", action="store_true",
+    )
+    args = parser.parse_args()
+
+    if args.file is sys.stdin:
+        args.inplace = False
+
+    with args.file:
+        if args.shell_split:
+            process(args, shlex.split, shlex.quote)
+        else:
+            process(args, str.split, str)
+
+
+if __name__ == "__main__":
+    main()

realign-spaces/test.sh

@@ -0,0 +1,62 @@
+#!/bin/sh -eu
+# SPDX-License-Identifier: WTFPL
+# shellcheck enable=
+
+cd "$(dirname "$0")"
+
+got=$(mktemp realign-spaces.XXXXXX)
+trap 'rm "$got"' EXIT
+
+
+init () {
+	./realign-spaces.py "$@" > "$got"
+}
+
+check () {
+	diff -u - "$got"
+}
+
+
+# basic test
+init <<- EOF
+	a bbb
+	aaaa b
+	c
+EOF
+
+check <<- EOF
+	a    bbb
+	aaaa b
+	c
+EOF
+
+# shell split
+init --shell-split <<- EOF
+	'a b' bbb
+	aaa b
+	c
+EOF
+
+check <<- EOF
+	'a b' bbb
+	aaa   b
+	c
+EOF
+
+# -i
+cat > "$got" <<- EOF
+	a bbb
+	aaa b
+	c
+EOF
+# set a weird mode to check umask does not affect it
+chmod 623 "$got"
+./realign-spaces.py -i "$got"
+
+check <<- EOF
+	a   bbb
+	aaa b
+	c
+EOF
+# check our mode was preserved
+ls -l "$got" | grep -q rw--w--wx