Better messages for partial indentation in L003 (#3634)

* Better messages for partial indentation in L003

* Calculate has_partial_indent in L003 once

Co-authored-by: Barry Hart <barrywhart@yahoo.com>

src/sqlfluff/rules/L003.py

@@ -5,13 +5,13 @@
 
 from sqlfluff.core.parser import WhitespaceSegment
 from sqlfluff.core.parser.segments import BaseSegment
-from sqlfluff.core.rules.functional import rsp, sp, Segments
-from sqlfluff.core.rules.base import BaseRule, LintResult, LintFix, RuleContext
+from sqlfluff.core.rules.base import BaseRule, LintFix, LintResult, RuleContext
 from sqlfluff.core.rules.doc_decorators import (
     document_configuration,
     document_fix_compatible,
     document_groups,
 )
+from sqlfluff.core.rules.functional import Segments, rsp, sp
 from sqlfluff.core.templaters import TemplatedFile
 from sqlfluff.core.templaters.base import RawFileSlice
 
@@ -513,7 +513,10 @@ def _process_working_state(
             return LintResult(memory=memory)
         prev_line_no = prev_line.line_no
         indent_diff = this_line.anchor_indent_balance - prev_line.anchor_indent_balance
-        this_indent_num = this_line.indent_size // self.tab_space_size
+        this_indent_num, this_indent_rem = divmod(
+            this_line.indent_size, self.tab_space_size
+        )
+        has_partial_indent = bool(this_indent_rem)
         comp_indent_num = prev_line.indent_size // self.tab_space_size
         # Is the indent balance the same?
         if indent_diff == 0:
@@ -548,6 +551,7 @@ def _process_working_state(
                     description=_Desc(
                         expected=comp_indent_num,
                         found=this_indent_num,
+                        has_partial_indent=has_partial_indent,
                         compared_to=prev_line.line_no,
                     ),
                     fixes=fixes,
@@ -596,6 +600,7 @@ def _process_working_state(
                     description=_Desc(
                         expected=len(desired_indent) // self.tab_space_size,
                         found=this_indent_num,
+                        has_partial_indent=has_partial_indent,
                         compared_to=prev_line.line_no,
                     ),
                     fixes=fixes,
@@ -634,6 +639,7 @@ def _process_working_state(
                         description=_Desc(
                             expected=this_indent_num + 1,
                             found=this_indent_num,
+                            has_partial_indent=has_partial_indent,
                             compared_to=prev_line.line_no,
                         ),
                         # Add in an extra bit of whitespace for the indent
@@ -672,6 +678,7 @@ def _process_working_state(
                     description=_Desc(
                         expected=comp_indent_num,
                         found=this_indent_num,
+                        has_partial_indent=has_partial_indent,
                         compared_to=prev_line.line_no,
                     ),
                     fixes=fixes,
@@ -1022,11 +1029,16 @@ def _find_matching_start_line(
 
 
 def _Desc(
-    expected: int,
-    found: int,
-    compared_to: int,
+    expected: int, found: int, compared_to: int, has_partial_indent: bool = False
 ) -> str:
+    indentations = "indentation" if expected == 1 else "indentations"
+    if found >= expected and has_partial_indent:
+        found_explanation = f"more than {found}"
+    elif found < expected and has_partial_indent:
+        found_explanation = f"less than {found + 1}"
+    else:
+        found_explanation = str(found)
     return (
-        f"Expected {expected} indentations,"
-        f" found {found} [compared to line {compared_to:02}]"
+        f"Expected {expected} {indentations},"
+        f" found {found_explanation} [compared to line {compared_to:02}]"
     )

test/cli/commands_test.py

@@ -7,24 +7,24 @@
 import re
 import shutil
 import stat
+import subprocess
+import sys
 import tempfile
 import textwrap
 from unittest.mock import MagicMock, patch
 
-import yaml
-import subprocess
 import chardet
-import sys
 
 # Testing libraries
 import pytest
+import yaml
 from click.testing import CliRunner
 
 # We import the library directly here to get the version
 import sqlfluff
-from sqlfluff.cli.commands import lint, version, rules, fix, parse, dialects, get_config
-from sqlfluff.core.rules.base import BaseRule, LintFix, LintResult
+from sqlfluff.cli.commands import dialects, fix, get_config, lint, parse, rules, version
 from sqlfluff.core.parser.segments.raw import CommentSegment
+from sqlfluff.core.rules.base import BaseRule, LintFix, LintResult
 
 re_ansi_escape = re.compile(r"\x1b[^m]*m")
 
@@ -62,7 +62,8 @@ def invoke_assert_code(
 
 
 expected_output = """== [test/fixtures/linter/indentation_error_simple.sql] FAIL
-L:   2 | P:   4 | L003 | Expected 1 indentations, found 0 [compared to line 01]
+L:   2 | P:   4 | L003 | Expected 1 indentation, found less than 1 [compared to
+                       | line 01]
 L:   5 | P:  10 | L010 | Keywords must be consistently upper case.
 L:   5 | P:  13 | L031 | Avoid aliases in from clauses and join conditions.
 """
@@ -1190,7 +1191,7 @@ def test__cli__command_lint_serialize_multiple_files(serialize, write_file, tmp_
         result_payload = result.output
 
     if serialize == "human":
-        assert len(result_payload.split("\n")) == 29 if write_file else 30
+        assert len(result_payload.split("\n")) == 33 if write_file else 32
     elif serialize == "json":
         result = json.loads(result_payload)
         assert len(result) == 2

test/rules/std_L003_test.py

@@ -1,7 +1,7 @@
 """Tests the python routines within L003."""
 import pytest
 
-from sqlfluff.rules.L003 import Rule_L003
+from sqlfluff.rules.L003 import Rule_L003, _Desc
 
 
 @pytest.mark.parametrize(
@@ -45,6 +45,39 @@ def is_type(self, *seg_type):
     ],
 )
 def test__rules__std_L003_indent_size(tab_space_size, segments, result):
-    """Test Rule_L003._make_indent."""
+    """Test Rule_L003._indent_size."""
     res = Rule_L003._indent_size(segments=segments, tab_space_size=tab_space_size)
     assert res == result
+
+
+@pytest.mark.parametrize(
+    "expected,found,compared_to,has_partial_indent,expected_message",
+    [
+        (
+            1,
+            1,
+            4,
+            True,
+            "Expected 1 indentation, found more than 1 [compared to line 04]",
+        ),
+        (
+            2,
+            1,
+            10,
+            False,
+            "Expected 2 indentations, found 1 [compared to line 10]",
+        ),
+        (
+            2,
+            1,
+            11,
+            True,
+            "Expected 2 indentations, found less than 2 [compared to line 11]",
+        ),
+    ],
+)
+def test__rules__std_L003_desc(
+    expected, found, compared_to, has_partial_indent, expected_message
+):
+    """Test Rule_L003 error description."""
+    assert _Desc(expected, found, compared_to, has_partial_indent) == expected_message