diagnostics: Support conversion of tabs to spaces [PR49973] [PR86904]

Supports conversion of tabs to spaces when outputting diagnostics. Also
adds -fdiagnostics-column-unit and -fdiagnostics-column-origin options to
control how the column number is output, thereby resolving the two PRs.

gcc/c-family/ChangeLog:

	PR other/86904
	* c-indentation.c (should_warn_for_misleading_indentation): Get
	global tabstop from the new source.
	* c-opts.c (c_common_handle_option): Remove handling of -ftabstop, which
	is now a common option.
	* c.opt: Likewise.

gcc/ChangeLog:

	PR preprocessor/49973
	PR other/86904
	* common.opt: Handle -ftabstop here instead of in c-family
	options.  Add -fdiagnostics-column-unit= and
	-fdiagnostics-column-origin= options.
	* opts.c (common_handle_option): Handle the new options.
	* diagnostic-format-json.cc (json_from_expanded_location): Add
	diagnostic_context argument.  Use it to convert column numbers as per
	the new options.
	(json_from_location_range): Likewise.
	(json_from_fixit_hint): Likewise.
	(json_end_diagnostic): Pass the new context argument to helper
	functions above.  Add "column-origin" field to the output.
	(test_unknown_location): Add the new context argument to calls to
	helper functions.
	(test_bad_endpoints): Likewise.
	* diagnostic-show-locus.c
	(exploc_with_display_col::exploc_with_display_col): Support
	tabstop parameter.
	(layout_point::layout_point): Make use of class
	exploc_with_display_col.
	(layout_range::layout_range): Likewise.
	(struct line_bounds): Clarify that the units are now always
	display columns.  Rename members accordingly.  Add constructor.
	(layout::print_source_line): Add support for tab expansion.
	(make_range): Adapt to class layout_range changes.
	(layout::maybe_add_location_range): Likewise.
	(layout::layout): Adapt to class exploc_with_display_col changes.
	(layout::calculate_x_offset_display): Support tabstop parameter.
	(layout::print_annotation_line): Adapt to struct line_bounds changes.
	(layout::print_line): Likewise.
	(line_label::line_label): Add diagnostic_context argument.
	(get_affected_range): Likewise.
	(get_printed_columns): Likewise.
	(layout::print_any_labels): Adapt to struct line_label changes.
	(class correction): Add m_tabstop member.
	(correction::correction): Add tabstop argument.
	(correction::compute_display_cols): Use m_tabstop.
	(class line_corrections): Add m_context member.
	(line_corrections::line_corrections): Add diagnostic_context argument.
	(line_corrections::add_hint): Use m_context to handle tabstops.
	(layout::print_trailing_fixits): Adapt to class line_corrections
	changes.
	(test_layout_x_offset_display_utf8): Support tabstop parameter.
	(test_layout_x_offset_display_tab): New selftest.
	(test_one_liner_colorized_utf8): Likewise.
	(test_tab_expansion): Likewise.
	(test_diagnostic_show_locus_one_liner_utf8): Call the new tests.
	(diagnostic_show_locus_c_tests): Likewise.
	(test_overlapped_fixit_printing): Adapt to helper class and
	function changes.
	(test_overlapped_fixit_printing_utf8): Likewise.
	(test_overlapped_fixit_printing_2): Likewise.
	* diagnostic.h (enum diagnostics_column_unit): New enum.
	(struct diagnostic_context): Add members for the new options.
	(diagnostic_converted_column): Declare.
	(json_from_expanded_location): Add new context argument.
	* diagnostic.c (diagnostic_initialize): Initialize new members.
	(diagnostic_converted_column): New function.
	(maybe_line_and_column): Be willing to output a column of 0.
	(diagnostic_get_location_text): Convert column number as per the new
	options.
	(diagnostic_report_current_module): Likewise.
	(assert_location_text): Add origin and column_unit arguments for
	testing the new functionality.
	(test_diagnostic_get_location_text): Test the new functionality.
	* doc/invoke.texi: Document the new options and behavior.
	* input.h (location_compute_display_column): Add tabstop argument.
	* input.c (location_compute_display_column): Likewise.
	(test_cpp_utf8): Add selftests for tab expansion.
	* tree-diagnostic-path.cc (default_tree_make_json_for_path): Pass the
	new context argument to json_from_expanded_location().

libcpp/ChangeLog:

	PR preprocessor/49973
	PR other/86904
	* include/cpplib.h (struct cpp_options):  Removed support for -ftabstop,
	which is now handled by diagnostic_context.
	(class cpp_display_width_computation): New class.
	(cpp_byte_column_to_display_column): Add optional tabstop argument.
	(cpp_display_width): Likewise.
	(cpp_display_column_to_byte_column): Likewise.
	* charset.c
	(cpp_display_width_computation::cpp_display_width_computation): New
	function.
	(cpp_display_width_computation::advance_display_cols): Likewise.
	(compute_next_display_width): Removed and implemented this
	functionality in a new function...
	(cpp_display_width_computation::process_next_codepoint): ...here.
	(cpp_byte_column_to_display_column): Added tabstop argument.
	Reimplemented in terms of class cpp_display_width_computation.
	(cpp_display_column_to_byte_column): Likewise.
	* init.c (cpp_create_reader): Remove handling of -ftabstop, which is now
	handled by diagnostic_context.

gcc/testsuite/ChangeLog:

	PR preprocessor/49973
	PR other/86904
	* c-c++-common/Wmisleading-indentation-3.c: Adjust expected output
	for new defaults.
	* c-c++-common/Wmisleading-indentation.c: Likewise.
	* c-c++-common/diagnostic-format-json-1.c: Likewise.
	* c-c++-common/diagnostic-format-json-2.c: Likewise.
	* c-c++-common/diagnostic-format-json-3.c: Likewise.
	* c-c++-common/diagnostic-format-json-4.c: Likewise.
	* c-c++-common/diagnostic-format-json-5.c: Likewise.
	* c-c++-common/missing-close-symbol.c: Likewise.
	* g++.dg/diagnostic/bad-binary-ops.C: Likewise.
	* g++.dg/parse/error4.C: Likewise.
	* g++.old-deja/g++.brendan/crash11.C: Likewise.
	* g++.old-deja/g++.pt/overload2.C: Likewise.
	* g++.old-deja/g++.robertl/eb109.C: Likewise.
	* gcc.dg/analyzer/malloc-paths-9.c: Likewise.
	* gcc.dg/bad-binary-ops.c: Likewise.
	* gcc.dg/format/branch-1.c: Likewise.
	* gcc.dg/format/pr79210.c: Likewise.
	* gcc.dg/plugin/diagnostic-test-expressions-1.c: Likewise.
	* gcc.dg/plugin/diagnostic-test-string-literals-1.c: Likewise.
	* gcc.dg/redecl-4.c: Likewise.
	* gfortran.dg/diagnostic-format-json-1.F90: Likewise.
	* gfortran.dg/diagnostic-format-json-2.F90: Likewise.
	* gfortran.dg/diagnostic-format-json-3.F90: Likewise.
	* go.dg/arrayclear.go: Add a comment explaining why adding a
	comment was necessary to work around a dejagnu bug.
	* c-c++-common/diagnostic-units-1.c: New test.
	* c-c++-common/diagnostic-units-2.c: New test.
	* c-c++-common/diagnostic-units-3.c: New test.
	* c-c++-common/diagnostic-units-4.c: New test.
	* c-c++-common/diagnostic-units-5.c: New test.
	* c-c++-common/diagnostic-units-6.c: New test.
	* c-c++-common/diagnostic-units-7.c: New test.
	* c-c++-common/diagnostic-units-8.c: New test.

1 files changed, 33 insertions, 7 deletions

diff --git a/libcpp/include/cpplib.h b/libcpp/include/cpplib.h
index e8bb15d..8e39886 100644
--- a/libcpp/include/cpplib.h
+++ b/libcpp/include/cpplib.h
@@ -312,9 +312,6 @@ enum cpp_normalize_level {
    carries all the options visible to the command line.  */
 struct cpp_options
 {
-  /* Characters between tab stops.  */
-  unsigned int tabstop;
-
   /* The language we're preprocessing.  */
   enum c_lang lang;
 
@@ -1335,14 +1332,43 @@ extern const char * cpp_get_userdef_suffix
   (const cpp_token *);
 
 /* In charset.c */
+
+/* A class to manage the state while converting a UTF-8 sequence to cppchar_t
+   and computing the display width one character at a time.  */
+class cpp_display_width_computation {
+ public:
+  cpp_display_width_computation (const char *data, int data_length,
+				 int tabstop);
+  const char *next_byte () const { return m_next; }
+  int bytes_processed () const { return m_next - m_begin; }
+  int bytes_left () const { return m_bytes_left; }
+  bool done () const { return !bytes_left (); }
+  int display_cols_processed () const { return m_display_cols; }
+
+  int process_next_codepoint ();
+  int advance_display_cols (int n);
+
+ private:
+  const char *const m_begin;
+  const char *m_next;
+  size_t m_bytes_left;
+  const int m_tabstop;
+  int m_display_cols;
+};
+
+/* Convenience functions that are simple use cases for class
+   cpp_display_width_computation.  Tab characters will be expanded to spaces
+   as determined by TABSTOP.  */
 int cpp_byte_column_to_display_column (const char *data, int data_length,
-				       int column);
-inline int cpp_display_width (const char *data, int data_length)
+				       int column, int tabstop);
+inline int cpp_display_width (const char *data, int data_length,
+			      int tabstop)
 {
-    return cpp_byte_column_to_display_column (data, data_length, data_length);
+  return cpp_byte_column_to_display_column (data, data_length, data_length,
+					    tabstop);
 }
 int cpp_display_column_to_byte_column (const char *data, int data_length,
-				       int display_col);
+				       int display_col, int tabstop);
 int cpp_wcwidth (cppchar_t c);
 
 #endif /* ! LIBCPP_CPPLIB_H */