1 files changed, 130 insertions, 0 deletions
diff --git a/python/mozlint/mozlint/parser.py b/python/mozlint/mozlint/parser.py
new file mode 100644
index 0000000000..eac502495b
--- /dev/null
+++ b/python/mozlint/mozlint/parser.py
@@ -0,0 +1,130 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+import os
+
+import yaml
+
+from .errors import LinterNotFound, LinterParseError
+from .types import supported_types
+
+GLOBAL_SUPPORT_FILES = []
+
+
+class Parser(object):
+    """Reads and validates lint configuration files."""
+
+    required_attributes = (
+        "name",
+        "description",
+        "type",
+        "payload",
+    )
+
+    def __init__(self, root):
+        self.root = root
+
+    def __call__(self, path):
+        return self.parse(path)
+
+    def _validate(self, linter):
+        relpath = os.path.relpath(linter["path"], self.root)
+
+        missing_attrs = []
+        for attr in self.required_attributes:
+            if attr not in linter:
+                missing_attrs.append(attr)
+
+        if missing_attrs:
+            raise LinterParseError(
+                relpath,
+                "Missing required attribute(s): " "{}".format(",".join(missing_attrs)),
+            )
+
+        if linter["type"] not in supported_types:
+            raise LinterParseError(relpath, "Invalid type '{}'".format(linter["type"]))
+
+        for attr in ("include", "exclude", "support-files"):
+            if attr not in linter:
+                continue
+
+            if not isinstance(linter[attr], list) or not all(
+                isinstance(a, str) for a in linter[attr]
+            ):
+                raise LinterParseError(
+                    relpath,
+                    "The {} directive must be a " "list of strings!".format(attr),
+                )
+            invalid_paths = set()
+            for path in linter[attr]:
+                if "*" in path:
+                    if attr == "include":
+                        raise LinterParseError(
+                            relpath,
+                            "Paths in the include directive cannot "
+                            "contain globs:\n  {}".format(path),
+                        )
+                    continue
+
+                abspath = path
+                if not os.path.isabs(abspath):
+                    abspath = os.path.join(self.root, path)
+
+                if not os.path.exists(abspath):
+                    invalid_paths.add("  " + path)
+
+            if invalid_paths:
+                raise LinterParseError(
+                    relpath,
+                    "The {} directive contains the following "
+                    "paths that don't exist:\n{}".format(
+                        attr, "\n".join(sorted(invalid_paths))
+                    ),
+                )
+
+        if "setup" in linter:
+            if linter["setup"].count(":") != 1:
+                raise LinterParseError(
+                    relpath,
+                    "The setup attribute '{!r}' must have the "
+                    "form 'module:object'".format(linter["setup"]),
+                )
+
+        if "extensions" in linter:
+            linter["extensions"] = [e.strip(".") for e in linter["extensions"]]
+
+    def parse(self, path):
+        """Read a linter and return its LINTER definition.
+
+        :param path: Path to the linter.
+        :returns: List of linter definitions ([dict])
+        :raises: LinterNotFound, LinterParseError
+        """
+        if not os.path.isfile(path):
+            raise LinterNotFound(path)
+
+        if not path.endswith(".yml"):
+            raise LinterParseError(
+                path, "Invalid filename, linters must end with '.yml'!"
+            )
+
+        with open(path) as fh:
+            configs = list(yaml.safe_load_all(fh))
+
+        if not configs:
+            raise LinterParseError(path, "No lint definitions found!")
+
+        linters = []
+        for config in configs:
+            for name, linter in config.items():
+                linter["name"] = name
+                linter["path"] = path
+                self._validate(linter)
+                linter.setdefault("support-files", []).extend(
+                    GLOBAL_SUPPORT_FILES + [path]
+                )
+                linter.setdefault("include", ["."])
+                linters.append(linter)
+
+        return linters