Use core column_unit for UTF-8 columns

linter.py

@@ -17,6 +17,7 @@
 
 
 class Cppcheck(Linter):
+    column_unit = 'utf8'
     cmd = CMD
     regex = REGEX
     error_stream = util.STREAM_BOTH  # linting errors are on stderr, exceptions like "file not found" on stdout
@@ -32,6 +33,7 @@ class Cppcheck(Linter):
 
 
 class CppcheckPlus(Linter):
+    column_unit = 'utf8'
     cmd = CMD
     regex = REGEX
     error_stream = util.STREAM_BOTH  # linting errors are on stderr, exceptions like "file not found" on stdout

tests/test_columns.py

@@ -0,0 +1,58 @@
+import importlib
+import unittest
+
+import sublime
+from SublimeLinter.lint.linter import VirtualView
+
+
+Linters = importlib.import_module('SublimeLinter-cppcheck.linter')
+
+# Captured cppcheck 2.21.0 output; accented characters and emoji count UTF-8 bytes.
+SOURCE = (
+    '#include <stdio.h>\n'
+    'int main(void) {\n'
+    '\tchar buf[4];\n'
+    '\tprintf("é😀"); buf[10] = 0;\n'
+    '\tint x = 5;\n'
+    '\tint *p = 0; *p = 1;\n'
+    '\treturn 0;\n'
+    '}\n'
+)
+OUTPUT = (
+    "m.c:4:23:error:arrayIndexOutOfBounds:Array 'buf[4]' accessed at index 10, which is out of bounds.\n"
+    "m.c:6:15:error:nullPointer:Null pointer dereference: p\n"
+    "m.c:4:28:style:unreadVariable:Variable 'buf[10]' is assigned a value that is never used.\n"
+    "m.c:5:8:style:unreadVariable:Variable 'x' is assigned a value that is never used.\n"
+)
+
+
+class TestColumns(unittest.TestCase):
+    def test_captured_ascii_and_unicode_diagnostics_both_classes(self):
+        lines = SOURCE.splitlines()
+        expected = [(3, lines[3].index('[10]'), '['), (5, lines[5].index('p = 1'), 'p'),
+                    (3, lines[3].index('= 0'), '='), (4, lines[4].index('= 5'), '=')]
+        self.assertDiagnostics(OUTPUT, SOURCE, expected)
+
+    def test_raw_byte_columns_exceed_line_length_both_classes(self):
+        source = '\tprintf("é😀😀😀😀"); buf[10] = 0;'
+        for column, text in [(35, '['), (40, '=')]:
+            with self.subTest(column=column):
+                output = 'm.c:1:{}:error:rule:problem'.format(column)
+                self.assertDiagnostics(output, source, [(0, source.index(text), text)])
+
+    def assertDiagnostics(self, output, source, expected):
+        for cls in (Linters.Cppcheck, Linters.CppcheckPlus):
+            with self.subTest(linter=cls.name):
+                linter = cls(sublime.View(0), {})
+                vv = VirtualView(source)
+                matches = list(linter.find_errors(output))
+                self.assertEqual(len(matches), len(expected))
+                for match, (line, col, text) in zip(matches, expected):
+                    match['filename'] = None
+                    error = linter.process_match(match, vv)
+                    self.assertIsNotNone(error)
+                    begin = vv.full_line(line)[0] + col
+                    self.assertEqual({k: error[k] for k in ('line', 'start', 'region', 'offending_text')}, {
+                        'line': line, 'start': col, 'region': sublime.Region(begin, begin + len(text)),
+                        'offending_text': text,
+                    })