Add initial unit testing for identify - with focuses on yield and raise edge cases currently handled by import sorting core

Author: timothycrosley

tests/unit/test_identify.py

@@ -0,0 +1,139 @@
+from io import StringIO
+from typing import List
+
+from isort import identify
+
+
+def imports_in_code(code: str, **kwargs) -> List[identify.Import]:
+    return list(identify.imports(StringIO(code, **kwargs)))
+
+
+def test_yield_edge_cases():
+    assert not imports_in_code(
+        """
+raise SomeException("Blah") \\
+    from exceptionsInfo.popitem()[1]
+"""
+    )
+    assert not imports_in_code(
+        """
+def generator_function():
+    yield \\
+        from other_function()[1]
+"""
+    )
+    assert (
+        len(
+            imports_in_code(
+                """
+# one
+
+# two
+
+
+def function():
+    # three \\
+    import b
+    import a
+"""
+            )
+        )
+        == 2
+    )
+    assert (
+        len(
+            imports_in_code(
+                """
+# one
+
+# two
+
+
+def function():
+    raise \\
+    import b
+    import a
+"""
+            )
+        )
+        == 1
+    )
+    assert not imports_in_code(
+        """
+def generator_function():
+    (
+     yield
+     from other_function()[1]
+    )
+"""
+    )
+    assert not imports_in_code(
+        """
+def generator_function():
+    (
+    (
+    ((((
+    (((((
+    ((
+    (((
+     yield
+
+
+
+     from other_function()[1]
+    )))))))))))))
+    )))
+"""
+    )
+    assert (
+        len(
+            imports_in_code(
+                """
+def generator_function():
+    import os
+
+    yield \\
+    from other_function()[1]
+"""
+            )
+        )
+        == 1
+    )
+
+    assert not imports_in_code(
+        """
+def generator_function():
+    (
+    (
+    ((((
+    (((((
+    ((
+    (((
+     yield
+"""
+    )
+    assert not imports_in_code(
+        """
+def generator_function():
+    (
+    (
+    ((((
+    (((((
+    ((
+    (((
+     raise (
+"""
+    )
+    assert not imports_in_code(
+        """
+def generator_function():
+    (
+    (
+    ((((
+    (((((
+    ((
+    (((
+     raise \\
+     from \\
+"""
+    )