Add 'engine/' from commit 'a8e37fc010'

git-subtree-dir: engine
git-subtree-mainline: b74841629e
git-subtree-split: a8e37fc010

engine/modules/gdscript/tests/scripts/parser/features/constants.gd

@@ -0,0 +1,13 @@
+func test():
+	const _TEST = 12 + 34 - 56 * 78
+	const _STRING = "yes"
+	const _VECTOR = Vector2(5, 6)
+	const _ARRAY = []
+	const _DICTIONARY = {"this": "dictionary"}
+	const _FLOAT1 = 1e2
+	const _FLOAT2 = 1E2
+
+	# Create user constants from built-in constants.
+	const _HELLO = PI + TAU
+	const _INFINITY = INF
+	const _NOT_A_NUMBER = NAN