check_compliance.py: Detect redundant document separators in bindings

Binding YAML documents are not concatenated together, so no '...'
document separators are needed. Flag it.

Signed-off-by: Ulf Magnusson <[email protected]>

Author: ulfalizer

scripts/check_compliance.py

@@ -724,6 +724,9 @@ def run(self):
                 self.check_kconfig_header(fname)
                 self.check_redundant_zephyr_source(fname)
 
+            if fname.startswith("dts/bindings/"):
+                self.check_redundant_document_separator(fname)
+
             if fname.endswith((".c", ".cpp", ".h", ".ld", ".py", ".rst",
                                ".yaml", ".yml")) or is_kconfig:
                 self.check_source_file(fname)
@@ -769,6 +772,15 @@ def check_redundant_zephyr_source(self, fname):
 instead. The $srctree environment variable already points to the Zephyr root,
 and all 'source's are relative to it.""".format(match.group(1), fname))
 
+    def check_redundant_document_separator(self, fname):
+        # Looks for redundant '...' document separators in bindings
+
+        with open(os.path.join(GIT_TOP, fname), encoding="utf-8") as f:
+            if re.search(r"^\.\.\.", f.read(), re.MULTILINE):
+                self.add_failure(f"""\
+Redundant '...' document separator in {fname}. Binding YAML files are never
+concatenated together, so no document separators are needed.""")
+
     def check_source_file(self, fname):
         # Generic nits related to various source files