#!/bin/sh
# tests/test_patch.sh - Tests for patch applet
_test_name="patch"
. "$(dirname "$0")/harness.sh"
_srcdir="$(cd "$(dirname "$0")/../src/patch/tests" && pwd)"

setup_tmpdir
PATCH="$VX patch"

echo "Running patch tests..."

# --- basic: apply unified diffs from various starting points ---
printf "a\nb\nc\nd\ne\nf\ng\nh\ni\n" > foo_full
printf "a\nb\nc\n" > foo_start
printf "g\nh\ni\n" > foo_end
printf "d\ne\nf\n" > foo_middle

$VX diff -u foo_start foo_full > foo_start2full.diff || true
$VX diff -u foo_end foo_full > foo_end2full.diff || true
$VX diff -u foo_middle foo_full > foo_mid2full.diff || true

# Each diff should be 12 lines (9 content lines + 3 header)
_lines=$(wc -l < foo_start2full.diff | tr -d ' ')
check_eq "$_lines" "12" "basic: start diff is 12 lines"

_lines=$(wc -l < foo_end2full.diff | tr -d ' ')
check_eq "$_lines" "12" "basic: end diff is 12 lines"

_lines=$(wc -l < foo_mid2full.diff | tr -d ' ')
check_eq "$_lines" "12" "basic: mid diff is 12 lines"

# Apply patches
$PATCH foo_start foo_start2full.diff -o foo_start2full >/dev/null 2>&1
check_exit "basic: apply start->full" 0 diff -q foo_start2full foo_full

$PATCH foo_end foo_end2full.diff -o foo_end2full >/dev/null 2>&1
check_exit "basic: apply end->full" 0 diff -q foo_end2full foo_full

$PATCH foo_middle foo_mid2full.diff -o foo_mid2full >/dev/null 2>&1
check_exit "basic: apply mid->full" 0 diff -q foo_mid2full foo_full

# --- limited context: PR74127 regression ---
check_exit "limited_ctx: bad diff rejected" 1 \
    $PATCH -o _.out "$_srcdir/PR74127.in" "$_srcdir/PR74127-repro.diff"

check_exit "limited_ctx: good diff accepted" 0 \
    $PATCH -o _.out "$_srcdir/PR74127.in" "$_srcdir/PR74127-good.diff"

# --- file creation ---
echo "x" > fc_foo
$VX diff -u /dev/null fc_foo > fc_foo.diff || true
rm fc_foo
$PATCH -s < fc_foo.diff >/dev/null 2>&1
check_exit "file_creation: creates file" 0 test -f fc_foo

# --- reverse removal ---
echo "x" > rev_foo
$VX diff -u /dev/null rev_foo > rev_foo.diff || true
$PATCH -Rs < rev_foo.diff >/dev/null 2>&1
check_exit "file_removal: file removed" 1 test -f rev_foo

summary