From b961f92eb7d5e2f07c190f0cc83ef7fbcba42961 Mon Sep 17 00:00:00 2001
From: David <david@zarel.net>
Date: Mon, 16 Jun 2025 19:31:06 +0200
Subject: [PATCH] fix: do not mutate std.removeAt parameters

Resolves google/go-jsonnet#807
---
 builtins.go                             | 4 +++-
 testdata/builtinRemoveAt2.golden        | 7 +++++++
 testdata/builtinRemoveAt2.jsonnet       | 3 +++
 testdata/builtinRemoveAt2.linter.golden | 0
 4 files changed, 13 insertions(+), 1 deletion(-)
 create mode 100644 testdata/builtinRemoveAt2.golden
 create mode 100644 testdata/builtinRemoveAt2.jsonnet
 create mode 100644 testdata/builtinRemoveAt2.linter.golden

diff --git a/builtins.go b/builtins.go
index 421d5d3..7843d55 100644
--- a/builtins.go
+++ b/builtins.go
@@ -2485,6 +2485,7 @@ func builtinRemove(i *interpreter, arrv value, ev value) (value, error) {
 }
 
 func builtinRemoveAt(i *interpreter, arrv value, idxv value) (value, error) {
+	var newArr []*cachedThunk
 	arr, err := i.getArray(arrv)
 	if err != nil {
 		return nil, err
@@ -2494,7 +2495,8 @@ func builtinRemoveAt(i *interpreter, arrv value, idxv value) (value, error) {
 		return nil, err
 	}
 
-	newArr := append(arr.elements[:idx], arr.elements[idx+1:]...)
+	newArr = append(newArr, arr.elements[:idx]...)
+	newArr = append(newArr, arr.elements[idx+1:]...)
 	return makeValueArray(newArr), nil
 }
 
diff --git a/testdata/builtinRemoveAt2.golden b/testdata/builtinRemoveAt2.golden
new file mode 100644
index 0000000..7683a3f
--- /dev/null
+++ b/testdata/builtinRemoveAt2.golden
@@ -0,0 +1,7 @@
+[
+   "quux",
+   "foo",
+   "bar",
+   "foo",
+   "bar"
+]
diff --git a/testdata/builtinRemoveAt2.jsonnet b/testdata/builtinRemoveAt2.jsonnet
new file mode 100644
index 0000000..cfdb1ff
--- /dev/null
+++ b/testdata/builtinRemoveAt2.jsonnet
@@ -0,0 +1,3 @@
+local a = ['quux','foo','bar'];
+local b = std.removeAt(a,0);
+a+b
\ No newline at end of file
diff --git a/testdata/builtinRemoveAt2.linter.golden b/testdata/builtinRemoveAt2.linter.golden
new file mode 100644
index 0000000..e69de29