From c2f4e0e826fdc9e60ac73269ac89bddb709a1671 Mon Sep 17 00:00:00 2001
From: Kamil Kozik <kkozik@amplify.com>
Date: Wed, 19 Jun 2024 11:22:19 +0200
Subject: [PATCH] AT-11673 - additional test coverage part #1

---
 test/helpers/hcl2_helper.py   |  21 +++++
 test/unit/test_hcl2_syntax.py | 153 ++++++++++++++++++++++++++++++++++
 2 files changed, 174 insertions(+)
 create mode 100644 test/helpers/hcl2_helper.py
 create mode 100644 test/unit/test_hcl2_syntax.py

diff --git a/test/helpers/hcl2_helper.py b/test/helpers/hcl2_helper.py
new file mode 100644
index 00000000..f91edaf9
--- /dev/null
+++ b/test/helpers/hcl2_helper.py
@@ -0,0 +1,21 @@
+# pylint:disable=C0114,C0115,C0116
+
+from lark import Tree
+
+from hcl2.parser import hcl2
+from hcl2.transformer import DictTransformer
+
+
+class Hcl2Helper:
+    @classmethod
+    def load(cls, syntax: str) -> Tree:
+        return hcl2.parse(syntax)
+
+    @classmethod
+    def load_to_dict(cls, syntax) -> dict:
+        tree = cls.load(syntax)
+        return DictTransformer().transform(tree)
+
+    @classmethod
+    def build_argument(cls, identifier: str, expression: str = '"expression"') -> str:
+        return f"{identifier} = {expression}"
diff --git a/test/unit/test_hcl2_syntax.py b/test/unit/test_hcl2_syntax.py
new file mode 100644
index 00000000..3e6f19d0
--- /dev/null
+++ b/test/unit/test_hcl2_syntax.py
@@ -0,0 +1,153 @@
+# pylint:disable=C0114,C0116,C0103,W0612
+
+import string  # pylint:disable=W4901 # https://stackoverflow.com/a/16651393
+from unittest import TestCase
+
+from test.helpers.hcl2_helper import Hcl2Helper
+
+from lark import UnexpectedToken, UnexpectedCharacters
+
+
+class TestHcl2Syntax(Hcl2Helper, TestCase):
+    """Test parsing individual elements of HCL2 syntax"""
+
+    def test_argument(self):
+        syntax = self.build_argument("identifier", '"expression"')
+        result = self.load_to_dict(syntax)
+        self.assertDictEqual(result, {"identifier": "expression"})
+
+    def test_identifier_starts_with_digit(self):
+        for i in range(0, 10):
+            argument = self.build_argument(f"{i}id")
+            with self.assertRaises(UnexpectedToken) as e:
+                self.load_to_dict(argument)
+                assert (
+                    f"Unexpected token Token('DECIMAL', '{i}') at line 1, column 1"
+                    in str(e)
+                )
+
+    def test_identifier_starts_with_special_chars(self):
+        chars = string.punctuation.replace("_", "")
+        for i in chars:
+            argument = self.build_argument(f"{i}id")
+            with self.assertRaises((UnexpectedToken, UnexpectedCharacters)) as e:
+                self.load_to_dict(argument)
+
+    def test_identifier_contains_special_chars(self):
+        chars = string.punctuation.replace("_", "").replace("-", "")
+        for i in chars:
+            argument = self.build_argument(f"identifier{i}")
+            with self.assertRaises((UnexpectedToken, UnexpectedCharacters)) as e:
+                self.load_to_dict(argument)
+
+    def test_identifier(self):
+        argument = self.build_argument("_-__identifier_-1234567890-_")
+        self.load_to_dict(argument)
+
+    def test_block_no_labels(self):
+        block = """
+        block {
+        }
+        """
+        result = self.load_to_dict(block)
+        self.assertDictEqual(result, {"block": [{}]})
+
+    def test_block_single_label(self):
+        block = """
+        block "label" {
+        }
+        """
+        result = self.load_to_dict(block)
+        self.assertDictEqual(result, {"block": [{"label": {}}]})
+
+    def test_block_multiple_labels(self):
+        block = """
+        block "label1" "label2" "label3" {
+        }
+        """
+        result = self.load_to_dict(block)
+        self.assertDictEqual(
+            result, {"block": [{"label1": {"label2": {"label3": {}}}}]}
+        )
+
+    def test_unary_operation(self):
+        operations = [
+            ("identifier = -10", {"identifier": "${-10}"}),
+            ("identifier = !true", {"identifier": "${!True}"}),
+        ]
+        for hcl, dict_ in operations:
+            result = self.load_to_dict(hcl)
+            self.assertDictEqual(result, dict_)
+
+    def test_tuple(self):
+        tuple_ = """tuple = [
+        identifier,
+        "string", 100,
+        true == false,
+        5 + 5, function(),
+        ]"""
+        result = self.load_to_dict(tuple_)
+        self.assertDictEqual(
+            result,
+            {
+                "tuple": [
+                    "${identifier}",
+                    "string",
+                    100,
+                    "${True == False}",
+                    "${5 + 5}",
+                    "${function()}",
+                ]
+            },
+        )
+
+    def test_object(self):
+        object_ = """object = {
+        key1: identifier, key2: "string", key3: 100,
+        key4: true == false,
+        key5: 5 + 5, key6: function(),
+        }"""
+        result = self.load_to_dict(object_)
+        self.assertDictEqual(
+            result,
+            {
+                "object": {
+                    "key1": "${identifier}",
+                    "key2": "string",
+                    "key3": 100,
+                    "key4": "${True == False}",
+                    "key5": "${5 + 5}",
+                    "key6": "${function()}",
+                }
+            },
+        )
+
+    def test_function_call_and_arguments(self):
+        calls = {
+            "r = function()": {"r": "${function()}"},
+            "r = function(arg1, arg2)": {"r": "${function(arg1, arg2)}"},
+            """r = function(
+                        arg1, arg2,
+                        arg3,
+                    )
+            """: {
+                "r": "${function(arg1, arg2, arg3)}"
+            },
+        }
+
+        for call, expected in calls.items():
+            result = self.load_to_dict(call)
+            self.assertDictEqual(result, expected)
+
+    def test_index(self):
+        indexes = {
+            "r = identifier[10]": {"r": "${identifier[10]}"},
+            "r = identifier.20": {
+                "r": "${identifier[2]}"
+            },  # TODO debug why `20` is parsed to `2`
+            """r = identifier["key"]""": {"r": '${identifier["key"]}'},
+            """r = identifier.key""": {"r": "${identifier.key}"},
+        }
+        for call, expected in indexes.items():
+            result = self.load_to_dict(call)
+            self.assertDictEqual(result, expected)