[feat] ClangTidy enables only selected checkers

Due to the previous commit every checker is either enabled or disabled.
This resulted very long analyzer commands in ClangTidy because every
checker was explicitly enabled or disabled in the clang-tidy invocation.
ClangTidy has a lot of checkers and also all compiler warnings listed by
diagtool are also considered as checkers.

The goal of this commit is to simplify the clang-tidy invocation command.
First we disable all checkers and enable only those that are necessary to
run:

clang-tidy -checks=-*,enabled1,enabled2...

This patch takes into account that clang-diagnostic-... checkers don't
turn on the corresponding warnings. They have to be enabled by -W...
compiler flag.

analyzer/codechecker_analyzer/analyzers/clangtidy/analyzer.py

@@ -16,7 +16,7 @@
 import re
 import shlex
 import subprocess
-from typing import List, Tuple
+from typing import Iterable, List, Set, Tuple
 
 import yaml
 
@@ -165,13 +165,55 @@ def get_warnings(env=None):
         raise
 
 
+def _add_asterisk_for_group(
+    subset_checkers: Iterable[str],
+    all_checkers: Set[str]
+) -> List[str]:
+    """
+    Since CodeChecker interprets checker name prefixes as checker groups, they
+    have to be added a '*' joker character when using them at clang-tidy
+    -checks flag. This function adds a '*' for each item in "checkers" if it's
+    a checker group, i.e. identified as a prefix for any checker name in
+    "all_checkers".
+    For example "readability-container" is a prefix of multiple checkers, so
+    this is converted to "readability-container-*". On the other hand
+    "performance-trivially-destructible" is a full checker name, so it remains
+    as is.
+    """
+    def is_group_prefix_of(prefix: str, long: str) -> bool:
+        """
+        Returns True if a checker(-group) name is prefix of another
+        checker name. For example bugprone-string is prefix of
+        bugprone-string-constructor but not of
+        bugprone-stringview-nullptr.
+        """
+        prefix_split = prefix.split('-')
+        long_split = long.split('-')
+        return prefix_split == long_split[:len(prefix_split)]
+
+    def need_asterisk(checker: str) -> bool:
+        return any(
+            is_group_prefix_of(checker, long) and checker != long
+            for long in all_checkers)
+
+    result = []
+
+    for checker in subset_checkers:
+        result.append(checker + ('*' if need_asterisk(checker) else ''))
+
+    return result
+
+
 class ClangTidy(analyzer_base.SourceAnalyzer):
     """
     Constructs the clang tidy analyzer commands.
     """
 
     ANALYZER_NAME = 'clang-tidy'
 
+    # Cache object for get_analyzer_checkers().
+    __analyzer_checkers = None
+
     @classmethod
     def analyzer_binary(cls):
         return analyzer_context.get_context() \
@@ -204,6 +246,9 @@ def get_analyzer_checkers(cls):
         Return the list of the all of the supported checkers.
         """
         try:
+            if cls.__analyzer_checkers:
+                return cls.__analyzer_checkers
+
             environ = analyzer_context.get_context().analyzer_env
             result = subprocess.check_output(
                 [cls.analyzer_binary(), "-list-checks", "-checks=*"],
@@ -217,6 +262,8 @@ def get_analyzer_checkers(cls):
                 ("clang-diagnostic-" + warning, "")
                 for warning in get_warnings(environ))
 
+            cls.__analyzer_checkers = checker_description
+
             return checker_description
         except (subprocess.CalledProcessError, OSError):
             return []
@@ -266,24 +313,30 @@ def get_checker_list(self, config) -> Tuple[List[str], List[str]]:
         clang-tidy and in some cases that would cause analysis error due to
         some ClangSA bug.
         """
-        checkers = []
-        # Usage of a set will remove compiler warnings and clang-diagnostics
-        # which are the same.
+        # clang-tidy emits reports from its check in the same format as
+        # compiler diagnostics (like unused variables, etc). This makes it a
+        # little difficult to distinguish compiler warnings and clang-tidy
+        # check warnings. The only clue is that compiler warnings are emitted
+        # as if they came from a check called clang-diagnostic- (e.g.
+        # -Wunused-variable will emit a warning under the name
+        # clang-diagnostic-unused-variable).
+
+        # There are two ways to disable a compiler warning in clang-tidy,
+        # either by -Wno- or -checks=-clang-diagnostic- (note the dash before
+        # clang-diagnostic!). However, there is only one way to enable them:
+        # through -W. Using -checks=clang-diagnostic- does not enable the
+        # warning, but undoes -checks=-clang-diagnostic-.
+
+        # Since we disable all checks by default via -checks=-*, in order to
+        # enable a compiler warning, we first have to undo the -checks level
+        # disable and then enable it, so we need both
+        # -checks=compiler-diagnostic- and -W.
         compiler_warnings = set()
+        enabled_checkers = set()
 
         has_checker_config = \
             config.checker_config and config.checker_config != '{}'
 
-        # Do not disable any clang-tidy checks explicitly, but don't run
-        # ClangSA checkers. ClangSA checkers are driven by an other
-        # analyzer in CodeChecker.
-        checkers.append('-clang-analyzer-*')
-
-        # For clang compiler warnings a correspoding
-        # clang-diagnostic error is generated by Clang tidy.
-        # They can be disabled by this glob -clang-diagnostic-*
-        checkers.append('clang-diagnostic-*')
-
         # Config handler stores which checkers are enabled or disabled.
         for checker_name, value in config.checks().items():
             state, _ = value
@@ -307,28 +360,34 @@ def get_checker_list(self, config) -> Tuple[List[str], List[str]]:
                                 "instead.")
                     if state == CheckerState.enabled:
                         compiler_warnings.add('-W' + warning_name)
+                        enabled_checkers.add(checker_name)
                     elif state == CheckerState.disabled:
                         if config.enable_all:
                             LOG.warning("Disabling compiler warning with "
                                         f"compiler flag '-d W{warning_name}' "
                                         "is not supported.")
-                        compiler_warnings.add('-Wno-' + warning_name)
                 # If a clang-diagnostic-... is enabled add it as a compiler
                 # warning as -W..., if it is disabled, tidy can suppress when
                 # specified in the -checks parameter list, so we add it there
                 # as -clang-diagnostic-... .
                 elif warning_type == CheckerType.analyzer:
                     if state == CheckerState.enabled:
                         compiler_warnings.add('-W' + warning_name)
-                    elif state == CheckerState.disabled:
-                        checkers.append('-' + checker_name)
+                        enabled_checkers.add(checker_name)
 
                 continue
 
             if state == CheckerState.enabled:
-                checkers.append(checker_name)
-            elif state == CheckerState.disabled:
-                checkers.append('-' + checker_name)
+                enabled_checkers.add(checker_name)
+
+        # By default all checkers are disabled and the enabled ones are added
+        # explicitly.
+        checkers = ['-*']
+
+        checkers += _add_asterisk_for_group(
+            enabled_checkers,
+            set(x[0] for x in ClangTidy.get_analyzer_checkers()))
+
         # -checks=-clang-analyzer-* option is added to the analyzer command by
         # default except when all analyzer config options come from .clang-tidy
         # file. The content of this file overrides every other custom config
@@ -385,7 +444,8 @@ def construct_analyzer_cmd(self, result_handler):
             analyzer_cmd.append('-Qunused-arguments')
 
             # Enable these compiler warnings by default.
-            analyzer_cmd.extend(['-Wall', '-Wextra'])
+            if not config.enable_all:
+                analyzer_cmd.extend(['-Wno-everything'])
 
             compile_lang = self.buildaction.lang
 

analyzer/tests/functional/analyze_and_parse/test_files/compiler_warning_no_warn.output → analyzer/tests/functional/analyze_and_parse/test_files/compiler_warning_default_checker_priority.output

@@ -18,11 +18,40 @@ CHECK#CodeChecker check --build "make compiler_warning_simple" --output $OUTPUT$
 [] - To store results use the "CodeChecker store" command.
 [] - See --help and the user guide for further options about parsing and storing the reports.
 [] - ----=================----
-Found no defects in compiler_warning.cpp
+[MEDIUM] compiler_warning.cpp:3:7: unused variable 'i' [clang-diagnostic-unused-variable]
+  int i;
+      ^
+
+Found 1 defect(s) in compiler_warning.cpp
+
+
+----==== Severity Statistics ====----
+----------------------------
+Severity | Number of reports
+----------------------------
+MEDIUM   |                 1
+----------------------------
+----=================----
+
+----==== Checker Statistics ====----
+---------------------------------------------------------------
+Checker name                     | Severity | Number of reports
+---------------------------------------------------------------
+clang-diagnostic-unused-variable | MEDIUM   |                 1
+---------------------------------------------------------------
+----=================----
+
+----==== File Statistics ====----
+----------------------------------------
+File name            | Number of reports
+----------------------------------------
+compiler_warning.cpp |                 1
+----------------------------------------
+----=================----
 
 ----======== Summary ========----
 ---------------------------------------------
 Number of processed analyzer result files | 1
-Number of analyzer reports                | 0
+Number of analyzer reports                | 1
 ---------------------------------------------
 ----=================----

analyzer/tests/functional/analyze_and_parse/test_files/context_free_hash_clang_tidy.output

@@ -1,7 +1,7 @@
 NORMAL#CodeChecker log --output $LOGFILE$ --build "make context_hash" --quiet
-NORMAL#CodeChecker analyze $LOGFILE$ --output $OUTPUT$ --report-hash=context-free --analyzers clang-tidy
+NORMAL#CodeChecker analyze $LOGFILE$ --output $OUTPUT$ --report-hash=context-free --analyzers clang-tidy --disable clang-diagnostic-unused-but-set-variable --disable clang-diagnostic-unused-but-set-parameter
 NORMAL#CodeChecker parse $OUTPUT$ --print-steps
-CHECK#CodeChecker check --build "make context_hash" --output $OUTPUT$ --quiet --print-steps --report-hash=context-free --analyzers clang-tidy
+CHECK#CodeChecker check --build "make context_hash" --output $OUTPUT$ --quiet --print-steps --report-hash=context-free --analyzers clang-tidy --disable clang-diagnostic-unused-but-set-variable --disable clang-diagnostic-unused-but-set-parameter
 --------------------------------------------------------------------------------
 [] - Starting build...
 [] - Using CodeChecker ld-logger.

analyzer/tests/functional/analyze_and_parse/test_files/context_free_hash_v2_clang_tidy.output

@@ -1,7 +1,7 @@
 NORMAL#CodeChecker log --output $LOGFILE$ --build "make context_hash" --quiet
-NORMAL#CodeChecker analyze $LOGFILE$ --output $OUTPUT$ --report-hash=context-free-v2 --analyzers clang-tidy
+NORMAL#CodeChecker analyze $LOGFILE$ --output $OUTPUT$ --report-hash=context-free-v2 --analyzers clang-tidy --disable clang-diagnostic-unused-but-set-variable --disable clang-diagnostic-unused-but-set-parameter
 NORMAL#CodeChecker parse $OUTPUT$ --print-steps
-CHECK#CodeChecker check --build "make context_hash" --output $OUTPUT$ --quiet --print-steps --report-hash=context-free-v2 --analyzers clang-tidy
+CHECK#CodeChecker check --build "make context_hash" --output $OUTPUT$ --quiet --print-steps --report-hash=context-free-v2 --analyzers clang-tidy --disable clang-diagnostic-unused-but-set-variable --disable clang-diagnostic-unused-but-set-parameter
 --------------------------------------------------------------------------------
 [] - Starting build...
 [] - Using CodeChecker ld-logger.

analyzer/tests/functional/analyze_and_parse/test_files/context_sensitive_hash_clang_tidy.output

@@ -1,7 +1,7 @@
 NORMAL#CodeChecker log --output $LOGFILE$ --build "make context_hash" --quiet
-NORMAL#CodeChecker analyze $LOGFILE$ --output $OUTPUT$ --analyzers clang-tidy
+NORMAL#CodeChecker analyze $LOGFILE$ --output $OUTPUT$ --analyzers clang-tidy --disable clang-diagnostic-unused-but-set-variable --disable clang-diagnostic-unused-but-set-parameter
 NORMAL#CodeChecker parse $OUTPUT$ --print-steps
-CHECK#CodeChecker check --build "make context_hash" --output $OUTPUT$ --quiet --print-steps --analyzers clang-tidy
+CHECK#CodeChecker check --build "make context_hash" --output $OUTPUT$ --quiet --print-steps --analyzers clang-tidy --disable clang-diagnostic-unused-but-set-variable --disable clang-diagnostic-unused-but-set-parameter
 --------------------------------------------------------------------------------
 [] - Starting build...
 [] - Using CodeChecker ld-logger.

analyzer/tests/functional/analyze_and_parse/test_files/diagnostic_message_hash_clang_tidy.output

@@ -1,7 +1,7 @@
 NORMAL#CodeChecker log --output $LOGFILE$ --build "make context_hash" --quiet
-NORMAL#CodeChecker analyze $LOGFILE$ --output $OUTPUT$ --report-hash=diagnostic-message --analyzers clang-tidy
+NORMAL#CodeChecker analyze $LOGFILE$ --output $OUTPUT$ --report-hash=diagnostic-message --analyzers clang-tidy --disable clang-diagnostic-unused-but-set-variable --disable clang-diagnostic-unused-but-set-parameter
 NORMAL#CodeChecker parse $OUTPUT$ --print-steps
-CHECK#CodeChecker check --build "make context_hash" --output $OUTPUT$ --quiet --print-steps --report-hash=diagnostic-message --analyzers clang-tidy
+CHECK#CodeChecker check --build "make context_hash" --output $OUTPUT$ --quiet --print-steps --report-hash=diagnostic-message --analyzers clang-tidy --disable clang-diagnostic-unused-but-set-variable --disable clang-diagnostic-unused-but-set-parameter
 --------------------------------------------------------------------------------
 [] - Starting build...
 [] - Using CodeChecker ld-logger.

analyzer/tests/functional/analyze_and_parse/test_files/source_code_comments.output

@@ -1,7 +1,7 @@
 NORMAL#CodeChecker log --output $LOGFILE$ --build "make source_code_comments" --quiet
-NORMAL#CodeChecker analyze $LOGFILE$ --output $OUTPUT$ --analyzers clang-tidy --enable bugprone-sizeof-expression
+NORMAL#CodeChecker analyze $LOGFILE$ --output $OUTPUT$ --analyzers clang-tidy --enable bugprone-sizeof-expression --disable clang-diagnostic-unused-value
 NORMAL#CodeChecker parse $OUTPUT$
-CHECK#CodeChecker check --build "make source_code_comments" --output $OUTPUT$ --quiet --analyzers clang-tidy --enable bugprone-sizeof-expression
+CHECK#CodeChecker check --build "make source_code_comments" --output $OUTPUT$ --quiet --analyzers clang-tidy --enable bugprone-sizeof-expression --disable clang-diagnostic-unused-value
 --------------------------------------------------------------------------------
 [] - Starting build...
 [] - Using CodeChecker ld-logger.

analyzer/tests/functional/analyze_and_parse/test_files/source_code_comments_all.output

@@ -1,7 +1,7 @@
 NORMAL#CodeChecker log --output $LOGFILE$ --build "make source_code_comments" --quiet
-NORMAL#CodeChecker analyze $LOGFILE$ --output $OUTPUT$ --analyzers clang-tidy --enable bugprone-sizeof-expression
+NORMAL#CodeChecker analyze $LOGFILE$ --output $OUTPUT$ --analyzers clang-tidy --enable bugprone-sizeof-expression --disable clang-diagnostic-unused-value
 NORMAL#CodeChecker parse $OUTPUT$ --review-status unreviewed confirmed false_positive intentional
-CHECK#CodeChecker check --build "make source_code_comments" --output $OUTPUT$ --quiet --analyzers clang-tidy --enable bugprone-sizeof-expression --review-status unreviewed confirmed false_positive intentional
+CHECK#CodeChecker check --build "make source_code_comments" --output $OUTPUT$ --quiet --analyzers clang-tidy --enable bugprone-sizeof-expression --disable clang-diagnostic-unused-value --review-status unreviewed confirmed false_positive intentional
 --------------------------------------------------------------------------------
 [] - Starting build...
 [] - Using CodeChecker ld-logger.

analyzer/tests/functional/analyze_and_parse/test_files/source_code_comments_all_empty_filter.output

@@ -1,7 +1,7 @@
 NORMAL#CodeChecker log --output $LOGFILE$ --build "make source_code_comments" --quiet
-NORMAL#CodeChecker analyze $LOGFILE$ --output $OUTPUT$ --analyzers clang-tidy --enable bugprone-sizeof-expression
+NORMAL#CodeChecker analyze $LOGFILE$ --output $OUTPUT$ --analyzers clang-tidy --enable bugprone-sizeof-expression --disable clang-diagnostic-unused-value
 NORMAL#CodeChecker parse $OUTPUT$ --review-status
-CHECK#CodeChecker check --build "make source_code_comments" --output $OUTPUT$ --quiet --analyzers clang-tidy --enable bugprone-sizeof-expression --review-status
+CHECK#CodeChecker check --build "make source_code_comments" --output $OUTPUT$ --quiet --analyzers clang-tidy --enable bugprone-sizeof-expression --disable clang-diagnostic-unused-value --review-status
 --------------------------------------------------------------------------------
 [] - Starting build...
 [] - Using CodeChecker ld-logger.

analyzer/tests/functional/analyze_and_parse/test_files/source_code_comments_confirmed.output

@@ -1,7 +1,7 @@
 NORMAL#CodeChecker log --output $LOGFILE$ --build "make source_code_comments" --quiet
-NORMAL#CodeChecker analyze $LOGFILE$ --output $OUTPUT$ --analyzers clang-tidy --enable bugprone-sizeof-expression
+NORMAL#CodeChecker analyze $LOGFILE$ --output $OUTPUT$ --analyzers clang-tidy --enable bugprone-sizeof-expression --disable clang-diagnostic-unused-value
 NORMAL#CodeChecker parse $OUTPUT$ --review-status confirmed
-CHECK#CodeChecker check --build "make source_code_comments" --output $OUTPUT$ --quiet --analyzers clang-tidy --enable bugprone-sizeof-expression --review-status confirmed
+CHECK#CodeChecker check --build "make source_code_comments" --output $OUTPUT$ --quiet --analyzers clang-tidy --enable bugprone-sizeof-expression --disable clang-diagnostic-unused-value --review-status confirmed
 --------------------------------------------------------------------------------
 [] - Starting build...
 [] - Using CodeChecker ld-logger.

analyzer/tests/functional/analyze_and_parse/test_files/source_code_comments_false_positive.output

@@ -1,7 +1,7 @@
 NORMAL#CodeChecker log --output $LOGFILE$ --build "make source_code_comments" --quiet
-NORMAL#CodeChecker analyze $LOGFILE$ --output $OUTPUT$ --analyzers clang-tidy --enable bugprone-sizeof-expression
+NORMAL#CodeChecker analyze $LOGFILE$ --output $OUTPUT$ --analyzers clang-tidy --enable bugprone-sizeof-expression --disable clang-diagnostic-unused-value
 NORMAL#CodeChecker parse $OUTPUT$ --review-status false_positive
-CHECK#CodeChecker check --build "make source_code_comments" --output $OUTPUT$ --quiet --analyzers clang-tidy --enable bugprone-sizeof-expression --review-status false_positive
+CHECK#CodeChecker check --build "make source_code_comments" --output $OUTPUT$ --quiet --analyzers clang-tidy --enable bugprone-sizeof-expression --disable clang-diagnostic-unused-value --review-status false_positive
 --------------------------------------------------------------------------------
 [] - Starting build...
 [] - Using CodeChecker ld-logger.

analyzer/tests/functional/analyze_and_parse/test_files/tidy_check.output

@@ -1,7 +1,7 @@
 NORMAL#CodeChecker log --output $LOGFILE$ --build "make tidy_check" --quiet
-NORMAL#CodeChecker analyze $LOGFILE$ --output $OUTPUT$ --analyzers clang-tidy --disable misc --enable bugprone-sizeof-expression
+NORMAL#CodeChecker analyze $LOGFILE$ --output $OUTPUT$ --analyzers clang-tidy --disable misc --enable bugprone-sizeof-expression --disable clang-diagnostic-unused-variable
 NORMAL#CodeChecker parse $OUTPUT$
-CHECK#CodeChecker check --build "make tidy_check" --output $OUTPUT$ --quiet --analyzers clang-tidy --disable misc --enable bugprone-sizeof-expression
+CHECK#CodeChecker check --build "make tidy_check" --output $OUTPUT$ --quiet --analyzers clang-tidy --disable misc --enable bugprone-sizeof-expression --disable clang-diagnostic-unused-variable
 --------------------------------------------------------------------------------
 [] - Starting build...
 [] - Using CodeChecker ld-logger.