bake: test indexof hcl func and make it private

Signed-off-by: CrazyMax <1951866+crazy-max@users.noreply.github.com>

bake/hcl_test.go

@@ -1445,6 +1445,39 @@ func TestVarUnsupportedType(t *testing.T) {
 	require.Error(t, err)
 }
 
+func TestHCLIndexOfFunc(t *testing.T) {
+	dt := []byte(`
+		variable "APP_VERSIONS" {
+		  default = [
+			"1.42.4",
+			"1.42.3"
+		  ]
+		}
+		target "default" {
+			args = {
+				APP_VERSION = app_version
+			}
+			matrix = {
+				app_version = APP_VERSIONS
+			}
+			name="app-${replace(app_version, ".", "-")}"
+			tags = [
+				"app:${app_version}",
+				indexof(APP_VERSIONS, app_version) == 0 ? "app:latest" : "",
+			]
+		}
+		`)
+
+	c, err := ParseFile(dt, "docker-bake.hcl")
+	require.NoError(t, err)
+
+	require.Equal(t, 2, len(c.Targets))
+	require.Equal(t, "app-1-42-4", c.Targets[0].Name)
+	require.Equal(t, "app:latest", c.Targets[0].Tags[1])
+	require.Equal(t, "app-1-42-3", c.Targets[1].Name)
+	require.Empty(t, c.Targets[1].Tags[1])
+}
+
 func ptrstr(s interface{}) *string {
 	var n *string
 	if reflect.ValueOf(s).Kind() == reflect.String {

bake/hclparser/stdlib.go

@@ -53,7 +53,7 @@ var stdlibFunctions = map[string]function.Function{
 	"hasindex":               stdlib.HasIndexFunc,
 	"indent":                 stdlib.IndentFunc,
 	"index":                  stdlib.IndexFunc,
-	"indexof":                IndexOfFunc, // behaving as expected by hcl definition of index (stdlib.IndexFunc is not compatible)
+	"indexof":                indexOfFunc,
 	"int":                    stdlib.IntFunc,
 	"join":                   stdlib.JoinFunc,
 	"jsondecode":             stdlib.JSONDecodeFunc,
@@ -117,10 +117,9 @@ var stdlibFunctions = map[string]function.Function{
 	"zipmap":                 stdlib.ZipmapFunc,
 }
 
-// IndexOfFunc constructs a function that finds the element index for a given value in a list.
-//
-// This function was imported from terraform's collection functions.
-var IndexOfFunc = function.New(&function.Spec{
+// indexOfFunc constructs a function that finds the element index for a given
+// value in a list.
+var indexOfFunc = function.New(&function.Spec{
 	Params: []function.Parameter{
 		{
 			Name: "list",

bake/hclparser/stdlib_test.go

@@ -0,0 +1,49 @@
+package hclparser
+
+import (
+	"testing"
+
+	"github.com/zclconf/go-cty/cty"
+)
+
+func TestIndexOf(t *testing.T) {
+	type testCase struct {
+		input   cty.Value
+		key     cty.Value
+		want    cty.Value
+		wantErr bool
+	}
+	tests := map[string]testCase{
+		"index 0": {
+			input: cty.TupleVal([]cty.Value{cty.StringVal("one"), cty.NumberIntVal(2.0), cty.NumberIntVal(3), cty.StringVal("four")}),
+			key:   cty.StringVal("one"),
+			want:  cty.NumberIntVal(0),
+		},
+		"index 3": {
+			input: cty.TupleVal([]cty.Value{cty.StringVal("one"), cty.NumberIntVal(2.0), cty.NumberIntVal(3), cty.StringVal("four")}),
+			key:   cty.StringVal("four"),
+			want:  cty.NumberIntVal(3),
+		},
+		"index -1": {
+			input:   cty.TupleVal([]cty.Value{cty.StringVal("one"), cty.NumberIntVal(2.0), cty.NumberIntVal(3), cty.StringVal("four")}),
+			key:     cty.StringVal("3"),
+			wantErr: true,
+		},
+	}
+
+	for name, test := range tests {
+		name, test := name, test
+		t.Run(name, func(t *testing.T) {
+			got, err := indexOfFunc.Call([]cty.Value{test.input, test.key})
+			if err != nil {
+				if test.wantErr {
+					return
+				}
+				t.Fatalf("unexpected error: %s", err)
+			}
+			if !got.RawEquals(test.want) {
+				t.Errorf("wrong result\ngot:  %#v\nwant: %#v", got, test.want)
+			}
+		})
+	}
+}