structpath: add NewPattern with AnyKey/AnyIndex wildcards

libs/structs/structpath/path.go

@@ -360,6 +360,37 @@ func NewPatternBracketStar(prev *PatternNode) *PatternNode {
 	})
 }
 
+// wildcard is a NewPattern part that matches any key or element.
+type wildcard int
+
+// Wildcards for [NewPattern]: AnyKey matches any map key or field (rendered ".*") and
+// AnyIndex matches any sequence element (rendered "[*]").
+const (
+	AnyKey   wildcard = tagDotStar
+	AnyIndex wildcard = tagBracketStar
+)
+
+// NewPattern appends parts to prev like [NewPath]; AnyKey and AnyIndex append wildcards.
+func NewPattern(prev *PatternNode, parts ...any) *PatternNode {
+	for _, part := range parts {
+		switch v := part.(type) {
+		case string:
+			prev = NewPatternStringKey(prev, v)
+		case int:
+			prev = NewPatternIndex(prev, v)
+		case wildcard:
+			if v == AnyKey {
+				prev = NewPatternDotStar(prev)
+			} else {
+				prev = NewPatternBracketStar(prev)
+			}
+		default:
+			panic(fmt.Sprintf("structpath.NewPattern: unsupported part %#v", part))
+		}
+	}
+	return prev
+}
+
 func NewPatternKeyValue(prev *PatternNode, key, value string) *PatternNode {
 	return (*PatternNode)(NewKeyValue((*PathNode)(prev), key, value))
 }

libs/structs/structpath/path_test.go

@@ -1297,3 +1297,13 @@ func TestNewPathSlice(t *testing.T) {
 	assert.Equal(t, "resources.jobs['${var.env}_job']", paths[0].String())
 	assert.Equal(t, "sync.paths[3]", NewPathSlice("sync", "paths", 3)[0].String())
 }
+
+func TestNewPattern(t *testing.T) {
+	p := NewPattern(nil, "resources", "jobs", AnyKey, "tasks", AnyIndex, "libraries")
+	assert.Equal(t, "resources.jobs.*.tasks[*].libraries", p.String())
+
+	ext := NewPattern(p, AnyIndex, "whl", 0)
+	assert.Equal(t, "resources.jobs.*.tasks[*].libraries[*].whl[0]", ext.String())
+
+	assert.Panics(t, func() { NewPattern(nil, 1.5) })
+}