test: add tests for component code segmentation

Further manual testing and concentrated code staring has been performed
for some edge cases.

tests/compiler/code/test_segment.py

@@ -0,0 +1,44 @@
+from unittest import TestCase
+from pathlib import Path
+from pyromaniac.compiler.code.segment.errors import (
+    InvalidSignatureError,
+    UnexpectedTokenError,
+)
+from pyromaniac.compiler.code.segment import segment
+
+
+class TestSegment(TestCase):
+    def setUp(self):
+        self.comps = Path(__file__).parent.parent.parent.joinpath("components")
+
+    def test_pure_yaml(self):
+        doc, sig, python, yaml = segment(self.load("qux.pyro"))
+        self.assertIsNotNone(yaml)
+        self.assertTupleEqual((doc, sig, python), (None, None, None))
+
+    def test_pure_python(self):
+        doc, sig, python, yaml = segment(self.load("quux.pyro"))
+        self.assertIsNotNone(python)
+        self.assertTupleEqual((doc, sig, yaml), (None, None, None))
+
+    def test_all(self):
+        doc, sig, python, yaml = segment(self.load("foo", "baz.pyro"))
+        self.assertIsNotNone(doc)
+        self.assertIsNotNone(sig)
+        self.assertIsNotNone(python)
+        self.assertIsNotNone(yaml)
+        self.assertTrue(python.splitlines()[8].startswith("message ="))
+        self.assertTrue(yaml.splitlines()[13].startswith("storage.files"))
+
+    def test_invalid_signature(self):
+        with self.assertRaises(InvalidSignatureError):
+            segment(self.load("bar", "main.pyro"))
+
+    def test_unexpected_token(self):
+        with self.assertRaises(UnexpectedTokenError) as ctx:
+            segment(self.load("bar", "fred.pyro"))
+        self.assertEqual(ctx.exception.line, 1)
+        self.assertEqual(ctx.exception.token.string, ')')
+
+    def load(self, *path: str) -> str:
+        return self.comps.joinpath(*path).read_text()

tests/components/bar/fred.pyro

@@ -1 +1 @@
-{}
+(foo: str))

tests/components/bar/main.pyro

@@ -1 +1,5 @@
-{}
+(name: str, age: int
+
+---
+
+{"message": f"Hello {age} year old {name}!"}

tests/components/foo/baz.pyro

@@ -1 +1,17 @@
-{}
+"""doc string""" # this is the doc string
+
+# Now comes the signature
+(name: str, age: int, *args: str, **kwargs: float) # this is the signature
+
+---
+
+# here we use string interpolation to construct a message
+message = f"Hello {age} year old {name}!"
+
+---
+
+# here comes the yaml code
+storage.files[0]:
+  path: /greeting.txt
+  contents.inline: {{ message }} # here we insert the message with jinja syntax
+  "hello"

tests/components/quux.pyro

@@ -1 +1,3 @@
-{}
+---
+path = "/directory"
+{"storage.directories[0].path": path}

tests/components/qux.pyro

@@ -1 +1 @@
-{}
+storage.files[0].path: /file.txt