Add support for coded source blocks

Author: gerlero

src/foamlib/_files/_parsing/_parser.py

@@ -527,7 +527,7 @@ def _parse_field(contents: bytes | bytearray, pos: int) -> tuple[Field, int]:
 
 def _parse_token(contents: bytes | bytearray, pos: int) -> tuple[str, int]:
     c = contents[pos : pos + 1]
-    if c.isalpha() or (c and c in b"_#$"):
+    if c.isalpha() or (c and c in b"_#$" and contents[pos + 1 : pos + 2] != b"{"):
         end = pos + 1
         depth = 0
         while end < len(contents):
@@ -568,6 +568,17 @@ def _parse_token(contents: bytes | bytearray, pos: int) -> tuple[str, int]:
                 end += 1
         raise FoamFileDecodeError(contents, pos, expected="end of quoted string")
 
+    if contents[pos : pos + 2] == b"#{":
+        end = pos + 2
+
+        while end < len(contents) and contents[end : end + 2] != b"#}":
+            end += 1
+
+        if end >= len(contents):
+            raise FoamFileDecodeError(contents, end, expected="#}")
+
+        return contents[pos : end + 2].decode(), end + 2
+
     raise ParseError(contents, pos, expected="token")
 
 

tests/test_files/test_parsing/test_coded.py

@@ -0,0 +1,19 @@
+from foamlib import FoamFile
+
+
+def test_issue_730() -> None:
+    file = {}
+    file["functions"] = {}
+    file["functions"]["difference"] = {
+        "type": "coded",
+        "libs": ["utilityFunctionObjects"],
+        "name": "writeMagU",
+        "codeWrite": '#{\
+        const volVectorField& U = mesh().lookupObject<volVectorField>("U");\
+        mag(U)().write();\
+    #}',
+    }
+
+    contents = FoamFile.dumps(file)
+    read = FoamFile.loads(contents)
+    assert read == file

tests/test_files/test_parsing/test_intermediate.py

@@ -310,7 +310,6 @@ def test_directives_in_dict() -> None:
     """)
 
 
-@pytest.mark.xfail(reason="Not currently supported")
 def test_code() -> None:
     ParsedFile(b"""
         code_name