1 files changed, 77 insertions, 0 deletions

diff --git a/lib/python/qmk/makefile.py b/lib/python/qmk/makefile.py
new file mode 100644
index 000000000..ce64431f9
--- /dev/null
+++ b/lib/python/qmk/makefile.py
@@ -0,0 +1,77 @@
+""" Functions for working with Makefiles
+"""
+import os
+import glob
+import re
+
+import qmk.path
+from qmk.errors import NoSuchKeyboardError
+
+def parse_rules_mk(file_path):
+    """ Parse a rules.mk file
+
+    Args:
+        file_path: path to the rules.mk file
+
+    Returns:
+        a dictionary with the file's content
+    """
+    # regex to match lines with comment at the end
+    # group(1) = option's name
+    # group(2) = operator (eg.: '=', '+=')
+    # group(3) = value(s)
+    commented_regex = re.compile(r"^\s*(\w+)\s*([\:\+\-]?=)\s*(.*?)(?=\s*\#)")
+    # regex to match lines without comment at the end
+    # group(1) = option's name
+    # group(2) = operator (eg.: '=', '+=')
+    # group(3) = value(s)
+    uncommented_regex = re.compile(r"^\s*(\w+)\s*([\:\+\-]?=)\s*(.*?)(?=\s*$)")
+    mk_content = qmk.path.unicode_lines(file_path)
+    parsed_file = dict()
+    for line in mk_content:
+        found = commented_regex.search(line) if "#" in line else uncommented_regex.search(line)
+        if found:
+            parsed_file[found.group(1)] = dict(operator = found.group(2), value = found.group(3))
+    return parsed_file
+
+def merge_rules_mk_files(base, revision):
+    """ Merge a keyboard revision's rules.mk file with
+    the 'base' rules.mk file
+
+    Args:
+        base: the base rules.mk file's content as dictionary
+        revision: the revision's rules.mk file's content as dictionary
+
+    Returns:
+        a dictionary with the merged content
+    """
+    return {**base, **revision}
+
+def get_rules_mk(keyboard, revision = ""):
+    """ Get a rules.mk for a keyboard
+
+    Args:
+        keyboard: name of the keyboard
+        revision: revision of the keyboard
+
+    Returns:
+        a dictionary with the content of the rules.mk file
+    """
+    base_path = os.path.join(os.getcwd(), "keyboards", keyboard) + os.path.sep
+    rules_mk = dict()
+    if os.path.exists(base_path + os.path.sep + revision):
+        rules_mk_path_wildcard = os.path.join(base_path, "**", "rules.mk")
+        rules_mk_regex = re.compile(r"^" + base_path + "(?:" + revision + os.path.sep + ")?rules.mk")
+        paths = [path for path in glob.iglob(rules_mk_path_wildcard, recursive = True) if rules_mk_regex.search(path)]
+        for file_path in paths:
+            rules_mk[revision if revision in file_path else "base"] = parse_rules_mk(file_path)
+    else:
+        raise NoSuchKeyboardError("The requested keyboard and/or revision does not exist.")
+
+    # if the base or the revision directory does not contain a rules.mk
+    if len(rules_mk) == 1:
+        rules_mk = rules_mk[revision]
+    # if both directories contain rules.mk files
+    elif len(rules_mk) == 2:
+        rules_mk = merge_rules_mk_files(rules_mk["base"], rules_mk[revision])
+    return rules_mk