Merge pull request #590 from gerlero/files

Improve parsing performance

Author: gerlero

foamlib/_files/_parsing/_elements.py

@@ -59,10 +59,20 @@ def parseImpl(
         self, instring: str, loc: int, doActions: bool = True
     ) -> tuple[int, ParseResults]:
         spacing_pattern = "|".join(re.escape(c) for c in self.whiteChars)
-        for ignore_expr in self.ignoreExprs:
-            assert isinstance(ignore_expr, Suppress)
-            assert isinstance(ignore_expr.expr, Regex)
-            spacing_pattern += f"|(?:{ignore_expr.expr.re.pattern})"
+        assert spacing_pattern
+
+        assert all(
+            isinstance(ignore_expr, Suppress) for ignore_expr in self.ignoreExprs
+        )
+        assert all(
+            isinstance(ignore_expr.expr, Regex) for ignore_expr in self.ignoreExprs
+        )
+        ignore_pattern = "|".join(
+            ignore_expr.expr.re.pattern for ignore_expr in self.ignoreExprs
+        )
+
+        if ignore_pattern:
+            spacing_pattern = f"{spacing_pattern}|{ignore_pattern}"
 
         if np.issubdtype(self._dtype, np.floating):
             base_pattern = self._FLOAT_PATTERN
@@ -86,7 +96,12 @@ def parseImpl(
         if match := regular_pattern.match(instring, pos=loc):
             count = int(c) if (c := match.group(1)) else None
             contents = match.group(2)
-            contents = re.sub(spacing_pattern, " ", contents)
+
+            if not all(c.isspace() for c in self.whiteChars):
+                contents = re.sub(spacing_pattern, " ", contents)
+            elif ignore_pattern:
+                contents = re.sub(ignore_pattern, " ", contents)  # Faster
+
             if self._elshape:
                 contents = contents.replace("(", " ").replace(")", " ")
 
@@ -206,10 +221,20 @@ def parseImpl(
         self, instring: str, loc: int, doActions: bool = True
     ) -> tuple[int, ParseResults]:
         spacing_pattern = "|".join(re.escape(c) for c in self.whiteChars)
-        for ignore_expr in self.ignoreExprs:
-            assert isinstance(ignore_expr, Suppress)
-            assert isinstance(ignore_expr.expr, Regex)
-            spacing_pattern += f"|(?:{ignore_expr.expr.re.pattern})"
+        assert spacing_pattern
+
+        assert all(
+            isinstance(ignore_expr, Suppress) for ignore_expr in self.ignoreExprs
+        )
+        assert all(
+            isinstance(ignore_expr.expr, Regex) for ignore_expr in self.ignoreExprs
+        )
+        ignore_pattern = "|".join(
+            ignore_expr.expr.re.pattern for ignore_expr in self.ignoreExprs
+        )
+
+        if ignore_pattern:
+            spacing_pattern = f"{spacing_pattern}|{ignore_pattern}"
 
         three_face_pattern = rf"3(?:{spacing_pattern})*\((?:{spacing_pattern})*(?:{self._INT_PATTERN}(?:{spacing_pattern})*){{3}}\)"
         four_face_pattern = rf"4(?:{spacing_pattern})*\((?:{spacing_pattern})*(?:{self._INT_PATTERN}(?:{spacing_pattern})*){{4}}\)"
@@ -224,7 +249,12 @@ def parseImpl(
         if match := face_list_pattern.match(instring, pos=loc):
             count = int(c) if (c := match.group(1)) else None
             contents = match.group(2)
-            contents = re.sub(spacing_pattern, " ", contents)
+
+            if not all(c.isspace() for c in self.whiteChars):
+                contents = re.sub(spacing_pattern, " ", contents)
+            elif ignore_pattern:
+                contents = re.sub(ignore_pattern, " ", contents)  # Faster
+
             contents = contents.replace("(", " ").replace(")", " ")
 
             raw = np.fromstring(contents, sep=" ", dtype=int)

tests/test_files/test_parsing/test_basic.py

@@ -52,6 +52,15 @@ def test_parse_value() -> None:
             [4, 5, 6],
         ],
     )
+    lst = Parsed(b"2((1\n2 3)\t(4 5 6))")[()]
+    assert isinstance(lst, np.ndarray)
+    assert np.array_equal(
+        lst,
+        [
+            [1, 2, 3],
+            [4, 5, 6],
+        ],
+    )
     lst = Parsed(b"2(3(1 2 3) 4(4 5 6 7))")[()]
     assert isinstance(lst, list)
     assert len(lst) == 2