fix(remote-job): a job name is data, never a shell pattern

`status` built its job list with `for n in $names`, which word-splits AND globs. The
second half is the bug: a job named `x*` was expanded against the caller's working
directory, so the report described unrelated files there as jobs and never mentioned
the one that ran — on a harness whose whole purpose is a report you can trust after
the session that started the job is gone. Splitting stays (several names in one
argument is the documented call shape); expansion goes.

`tail` was honest-by-accident in the wrong direction: with no jobs it handed a
literal `$JOBS/*.out` to tail, which reports a missing *file* — indistinguishable
from a broken tool — and a missing name produced tail's errno rather than "no job
called that". Both now say what is missing and exit 1.

Red first: the name test reads the report from a directory containing an unrelated
file, so the old glob is visible as a phantom job; both new tests fail against the
previous code and pass against this one.

Refs #60

omp-docs/tools/remote-job.md

@@ -38,10 +38,10 @@ read afterwards by a short-lived connection. That is what this is.
 
 ```bash
 remote-job.sh start NAME [--] CMD...   # launch detached, return at once
-remote-job.sh status [NAME]            # one line per job; exit 0 only if all DONE
+remote-job.sh status [NAME]            # one line per job; names literal, never globs
 remote-job.sh wait NAME [SEC] [N]      # block until DONE or timeout, then tail N lines
 remote-job.sh out NAME [N]             # tail a job's output
-remote-job.sh tail [NAME]              # follow one job, or every job at once
+remote-job.sh tail [NAME]              # follow one job, or all; exit 1 if nothing to follow
 remote-job.sh watch                    # refreshing status, for a spare pane
 ```
 
@@ -77,6 +77,7 @@ can be made from a fresh session on a machine that rebooted underneath it.
 | Command name is wrong | `PENDING (no output yet)`, exit 1 — never a false DONE |
 | Job exits non-zero | `DONE rc=N`; the code is data, not the report's status |
 | Two jobs, same NAME | the second replaces the first's state files |
+| `tail` with no job, or a name that is a glob | exit 1 saying there is nothing to follow; names are matched literally, never expanded |
 | Job dir missing | created on first use |
 
 Pinned by `tests/remote-job.bats` (black-box: output, exit codes, sentinel

scripts/remote-job.sh

@@ -51,13 +51,21 @@ case "${1:-}" in
     ;;
 
   status)
+    # Job names are data, never patterns. `for n in $names` word-split AND globbed: a job named
+    # `x*` was expanded against the caller's working directory, so the report described unrelated
+    # files there as jobs and never mentioned the one that ran. Splitting stays (several names in
+    # one argument is the documented call shape); expansion does not.
+    names=()
     if [[ -n "${2:-}" ]]; then
-      names="$2"
+      read -r -a names <<< "$2"
     else
-      names=$(cd "$JOBS" && ls *.out 2>/dev/null | sed 's/\.out$//' | sort)
+      while IFS= read -r -d '' f; do
+        names+=("$(basename "$f" .out)")
+      done < <(find "$JOBS" -maxdepth 1 -name '*.out' -print0 2>/dev/null | sort -z)
     fi
+    if [[ ${#names[@]} -eq 0 ]]; then echo "  (no jobs)"; exit 0; fi
     pending=0
-    for n in $names; do
+    for n in "${names[@]}"; do
       if [[ -f "$JOBS/$n.done" ]]; then
         printf '  %-20s DONE   rc=%s  %s lines\n' "$n" \
           "$(cat "$JOBS/$n.rc" 2>/dev/null)" "$(wc -l < "$JOBS/$n.out" 2>/dev/null | tr -d ' ')"
@@ -69,7 +77,6 @@ case "${1:-}" in
         pending=1
       fi
     done
-    if [[ -z "$names" ]]; then echo "  (no jobs)"; exit 0; fi
     exit "$pending"
     ;;
 
@@ -95,8 +102,15 @@ case "${1:-}" in
 
   tail)
     # Multiplexed follow: no NAME means every job at once, so one pane shows the whole harness.
-    if [[ -n "${2:-}" ]]; then exec tail -f "$JOBS/$2.out"; fi
+    # Both branches check for something to follow first: an unexpanded `*.out` handed to tail
-    exec tail -f "$JOBS"/*.out
+    # reports a missing *file*, which reads as a broken tool instead of an empty harness.
+    if [[ -n "${2:-}" ]]; then
+      [[ -f "$JOBS/$2.out" ]] || { echo "remote-job: no job '$2' (no $JOBS/$2.out)" >&2; exit 1; }
+      exec tail -f "$JOBS/$2.out"
+    fi
+    mapfile -d '' -t follow < <(find "$JOBS" -maxdepth 1 -name '*.out' -print0 2>/dev/null | sort -z)
+    (( ${#follow[@]} )) || { echo "remote-job: no jobs in $JOBS yet" >&2; exit 1; }
+    exec tail -f "${follow[@]}"
     ;;
 
   watch)

tests/remote-job.bats

@@ -122,6 +122,31 @@ until_done() {
   [[ "$output" == *38* ]]   # the tail, not the head
 }
 
+@test "status treats a job name as a name, not a pattern" {
+  "$SCRIPT" start 'x*' -- bash -c 'echo star'
+  until_done 'x*'
+  touch "$TEST_TMP/anchor"
+  # The report is read from a directory full of unrelated files on purpose: a name that is
+  # expanded as a glob resolves against the CALLER's cwd, so the tool would describe `anchor`
+  # as a job and never mention the one that really ran.
+  run bash -c 'cd "$1" && "$2" status "$3"' _ "$TEST_TMP" "$SCRIPT" 'x*'
+  [[ "$output" == "  x*"*"DONE   rc=0"* ]]
+  [[ "$output" != *anchor* ]]
+}
+
+@test "tail on an empty harness and on a missing job both say so" {
+  # An unexpanded `*.out` reaching tail is reported as a missing FILE, which reads as a broken
+  # script; the honest answer is that there is nothing to follow yet.
+  run timeout 5 "$SCRIPT" tail
+  [ "$status" -ne 0 ]
+  [[ "$output" == *"no jobs"* ]]
+  [[ "$output" != *".out"* ]]
+  run timeout 5 "$SCRIPT" tail nosuchjob
+  [ "$status" -ne 0 ]
+  [[ "$output" == *"nosuchjob"* ]]
+  [[ "$output" != *"No such file"* ]]
+}
+
 @test "an unknown verb is a usage error" {
   run "$SCRIPT" frobnicate
   [ "$status" -eq 2 ]