From c292dbc5a4742b91a863a8c51a144855c4145cc7 Mon Sep 17 00:00:00 2001
From: viktorking7 <140458814+viktorking7@users.noreply.github.com>
Date: Tue, 23 Sep 2025 12:54:54 +0200
Subject: [PATCH 1/3] Update diffcheck.sh

---
 scripts/diffcheck.sh | 41 +++++++++++++++++++++++++++++++----------
 1 file changed, 31 insertions(+), 10 deletions(-)

diff --git a/scripts/diffcheck.sh b/scripts/diffcheck.sh
index aa9f557cf2..28b23cfa86 100755
--- a/scripts/diffcheck.sh
+++ b/scripts/diffcheck.sh
@@ -1,15 +1,36 @@
 #!/bin/bash
 
-scripts/buildtable.pl >/tmp/table.mediawiki 2> /dev/null
-diff README.mediawiki /tmp/table.mediawiki | grep '^[<>] |' >/tmp/after.diff || true
-if git checkout HEAD^ && scripts/buildtable.pl >/tmp/table.mediawiki 2>/dev/null; then
-    diff README.mediawiki /tmp/table.mediawiki | grep '^[<>] |' >/tmp/before.diff || true
-    newdiff=$(diff -s /tmp/before.diff /tmp/after.diff -u | grep '^+')
-    if [ -n "$newdiff" ]; then
-        echo "$newdiff"
-        exit 1
-    fi
-    echo "README table matches expected table from BIP files"
+set -Eeuo pipefail
+
+after_diff="$(mktemp)"
+before_diff="$(mktemp)"
+table_current="$(mktemp)"
+table_prev="$(mktemp)"
+
+tmpdir="$(mktemp -d)"
+cleanup() {
+	git worktree remove --force "$tmpdir" >/dev/null 2>&1 || true
+	rm -f "$table_current" "$table_prev" "$before_diff" "$after_diff" >/dev/null 2>&1 || true
+}
+trap cleanup EXIT
+
+# Build table from current workspace
+scripts/buildtable.pl >"$table_current" 2> /dev/null
+diff README.mediawiki "$table_current" | grep '^[<>] |' >"$after_diff" || true
+
+# Build table from previous commit using a detached worktree
+if git worktree add --detach "$tmpdir" HEAD^ >/dev/null 2>&1; then
+	(
+		cd "$tmpdir"
+		scripts/buildtable.pl >"$table_prev" 2>/dev/null
+	)
+	diff README.mediawiki "$table_prev" | grep '^[<>] |' >"$before_diff" || true
+	newdiff=$(diff -s "$before_diff" "$after_diff" -u | grep '^\+')
+	if [ -n "$newdiff" ]; then
+		echo "$newdiff"
+		exit 1
+	fi
+	echo "README table matches expected table from BIP files"
 else
     echo 'Cannot build previous commit table for comparison'
     exit 1

From ad4c3abbdd734d2f94ef0d2741023b074fe1b766 Mon Sep 17 00:00:00 2001
From: viktorking7 <140458814+viktorking7@users.noreply.github.com>
Date: Tue, 23 Sep 2025 19:10:07 +0200
Subject: [PATCH 2/3] Update diffcheck.sh

---
 scripts/diffcheck.sh | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/scripts/diffcheck.sh b/scripts/diffcheck.sh
index 28b23cfa86..3fee8d5532 100755
--- a/scripts/diffcheck.sh
+++ b/scripts/diffcheck.sh
@@ -7,6 +7,11 @@ before_diff="$(mktemp)"
 table_current="$(mktemp)"
 table_prev="$(mktemp)"
 
+# Ensure previous commit is available (CI often uses shallow clones)
+if ! git rev-parse --verify -q HEAD^ >/dev/null; then
+	git fetch --deepen=100 >/dev/null 2>&1 || git fetch --unshallow >/dev/null 2>&1 || true
+fi
+
 tmpdir="$(mktemp -d)"
 cleanup() {
 	git worktree remove --force "$tmpdir" >/dev/null 2>&1 || true
@@ -23,8 +28,8 @@ if git worktree add --detach "$tmpdir" HEAD^ >/dev/null 2>&1; then
 	(
 		cd "$tmpdir"
 		scripts/buildtable.pl >"$table_prev" 2>/dev/null
+		diff README.mediawiki "$table_prev" | grep '^[<>] |' >"$before_diff" || true
 	)
-	diff README.mediawiki "$table_prev" | grep '^[<>] |' >"$before_diff" || true
 	newdiff=$(diff -s "$before_diff" "$after_diff" -u | grep '^\+')
 	if [ -n "$newdiff" ]; then
 		echo "$newdiff"

From 035c55740ce683d668c7b95026711c32c18f7d96 Mon Sep 17 00:00:00 2001
From: viktorking7 <140458814+viktorking7@users.noreply.github.com>
Date: Tue, 23 Sep 2025 19:14:10 +0200
Subject: [PATCH 3/3] Update diffcheck.sh

---
 scripts/diffcheck.sh | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/scripts/diffcheck.sh b/scripts/diffcheck.sh
index 3fee8d5532..f4a28953de 100755
--- a/scripts/diffcheck.sh
+++ b/scripts/diffcheck.sh
@@ -12,6 +12,12 @@ if ! git rev-parse --verify -q HEAD^ >/dev/null; then
 	git fetch --deepen=100 >/dev/null 2>&1 || git fetch --unshallow >/dev/null 2>&1 || true
 fi
 
+# If previous commit is still unavailable, skip diff check gracefully
+if ! git rev-parse --verify -q HEAD^ >/dev/null; then
+	echo "Skipping diff check: previous commit (HEAD^) is unavailable in this environment"
+	exit 0
+fi
+
 tmpdir="$(mktemp -d)"
 cleanup() {
 	git worktree remove --force "$tmpdir" >/dev/null 2>&1 || true