From ee908516796887afcaa1d9fabac80eae5a16c047 Mon Sep 17 00:00:00 2001 From: David Malcolm Date: Fri, 26 Aug 2016 21:25:41 +0000 Subject: Add validation and consolidation of fix-it hints MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The first aspect of this patch is to add some checking of fix-it hints. The idea is to put this checking within the rich_location machinery, rather than requiring every diagnostic to implement it for itself. The fixits within a rich_location are "atomic": all must be valid for any to be applicable. We reject any fixits involving locations above LINE_MAP_MAX_LOCATION_WITH_COLS. There's no guarantee that it's sane to modify a macro, so we reject any fix-its that touch them. For example, note the attempt to provide a fix-it for the definition of the macro FIELD: spellcheck-fields-2.c: In function ‘test_macro’: spellcheck-fields-2.c:26:15: error: ‘union u’ has no member named ‘colour’; did you mean ‘color’? #define FIELD colour ^ color spellcheck-fields-2.c:27:15: note: in expansion of macro ‘FIELD’ return ptr->FIELD; ^~~~~ After this patch, the fixit is not displayed: spellcheck-fields-2.c: In function ‘test_macro’: spellcheck-fields-2.c:26:15: error: ‘union u’ has no member named ‘colour’; did you mean ‘color’? #define FIELD colour ^ spellcheck-fields-2.c:27:15: note: in expansion of macro ‘FIELD’ return ptr->FIELD; ^~~~~ We might want some way for a diagnostic to opt-in to fix-its that affect macros, but for now it's simplest to reject them. The other aspect of this patch is fix-it consolidation: in some cases neighboring fix-its can be merged. For example, in a diagnostic to modernize old-style struct initializers from: struct s example = { - foo: 1, + .foo = 1, }; one approach would be to replace the "foo" with ".foo" and the ":" with " =". This would give two "replace" fix-its: foo: 1, --- FIXIT 1 .foo - FIXIT 2 = This patch allows them to be consolidated into a single "replace" fix-it: foo: 1, ---- .foo = gcc/ChangeLog: * diagnostic-show-locus.c (selftest::test_fixit_consolidation): New function. (selftest::diagnostic_show_locus_c_tests): Call it. * gcc-rich-location.h (gcc_rich_location): Eliminate unused constructor based on source_range. gcc/testsuite/ChangeLog: * gcc.dg/spellcheck-fields-2.c (test): Move dg-begin/end-multiline-output within function body. (test_macro): New function. libcpp/ChangeLog: * include/line-map.h (rich_location): Eliminate unimplemented constructor based on source_range. (rich_location::get_last_fixit_hint): New method. (rich_location::reject_impossible_fixit): New method. (rich_location): Add fields m_line_table and m_seen_impossible_fixit. (fixit_hint::maybe_append_replace): New pure virtual function. (fixit_insert::maybe_append_replace): New function. (fixit_replace::maybe_append_replace): New function. * line-map.c (rich_location::rich_location): Initialize m_line_table and m_seen_impossible_fixit. (rich_location::add_fixit_insert): Call reject_impossible_fixit and bail out if true. (column_before_p): New function. (rich_location::add_fixit_replace): Call reject_impossible_fixit and bail out if true. Attempt to consolidate with neighboring fixits. (rich_location::get_last_fixit_hint): New method. (rich_location::reject_impossible_fixit): New method. (fixit_insert::maybe_append_replace): New method. (fixit_replace::maybe_append_replace): New method. From-SVN: r239789 --- libcpp/ChangeLog | 24 ++++++++ libcpp/include/line-map.h | 19 ++++++- libcpp/line-map.c | 136 +++++++++++++++++++++++++++++++++++++++++++++- 3 files changed, 174 insertions(+), 5 deletions(-) (limited to 'libcpp') diff --git a/libcpp/ChangeLog b/libcpp/ChangeLog index 448d632..56971ad 100644 --- a/libcpp/ChangeLog +++ b/libcpp/ChangeLog @@ -1,3 +1,27 @@ +2016-08-26 David Malcolm + + * include/line-map.h (rich_location): Eliminate unimplemented + constructor based on source_range. + (rich_location::get_last_fixit_hint): New method. + (rich_location::reject_impossible_fixit): New method. + (rich_location): Add fields m_line_table and + m_seen_impossible_fixit. + (fixit_hint::maybe_append_replace): New pure virtual function. + (fixit_insert::maybe_append_replace): New function. + (fixit_replace::maybe_append_replace): New function. + * line-map.c (rich_location::rich_location): Initialize + m_line_table and m_seen_impossible_fixit. + (rich_location::add_fixit_insert): Call + reject_impossible_fixit and bail out if true. + (column_before_p): New function. + (rich_location::add_fixit_replace): Call reject_impossible_fixit + and bail out if true. Attempt to consolidate with neighboring + fixits. + (rich_location::get_last_fixit_hint): New method. + (rich_location::reject_impossible_fixit): New method. + (fixit_insert::maybe_append_replace): New method. + (fixit_replace::maybe_append_replace): New method. + 2016-08-23 David Malcolm * include/line-map.h (source_range::from_locations): New method. diff --git a/libcpp/include/line-map.h b/libcpp/include/line-map.h index a2ed008..0fc4848 100644 --- a/libcpp/include/line-map.h +++ b/libcpp/include/line-map.h @@ -1367,9 +1367,6 @@ class rich_location /* Constructing from a location. */ rich_location (line_maps *set, source_location loc); - /* Constructing from a source_range. */ - rich_location (source_range src_range); - /* Destructor. */ ~rich_location (); @@ -1411,12 +1408,17 @@ class rich_location unsigned int get_num_fixit_hints () const { return m_num_fixit_hints; } fixit_hint *get_fixit_hint (int idx) const { return m_fixit_hints[idx]; } + fixit_hint *get_last_fixit_hint () const; + +private: + bool reject_impossible_fixit (source_location where); public: static const int MAX_RANGES = 3; static const int MAX_FIXIT_HINTS = 2; protected: + line_maps *m_line_table; unsigned int m_num_ranges; location_range m_ranges[MAX_RANGES]; @@ -1427,6 +1429,7 @@ protected: unsigned int m_num_fixit_hints; fixit_hint *m_fixit_hints[MAX_FIXIT_HINTS]; + bool m_seen_impossible_fixit; }; class fixit_hint @@ -1440,6 +1443,10 @@ public: virtual bool affects_line_p (const char *file, int line) = 0; virtual source_location get_start_loc () const = 0; virtual bool maybe_get_end_loc (source_location *out) const = 0; + /* Vfunc for consolidating successor fixits. */ + virtual bool maybe_append_replace (line_maps *set, + source_range src_range, + const char *new_content) = 0; }; class fixit_insert : public fixit_hint @@ -1452,6 +1459,9 @@ class fixit_insert : public fixit_hint bool affects_line_p (const char *file, int line); source_location get_start_loc () const { return m_where; } bool maybe_get_end_loc (source_location *) const { return false; } + bool maybe_append_replace (line_maps *set, + source_range src_range, + const char *new_content); source_location get_location () const { return m_where; } const char *get_string () const { return m_bytes; } @@ -1478,6 +1488,9 @@ class fixit_replace : public fixit_hint *out = m_src_range.m_finish; return true; } + bool maybe_append_replace (line_maps *set, + source_range src_range, + const char *new_content); source_range get_range () const { return m_src_range; } const char *get_string () const { return m_bytes; } diff --git a/libcpp/line-map.c b/libcpp/line-map.c index 3890eff..8fe48bd 100644 --- a/libcpp/line-map.c +++ b/libcpp/line-map.c @@ -1959,11 +1959,13 @@ source_range::intersects_line_p (const char *file, int line) const /* Construct a rich_location with location LOC as its initial range. */ -rich_location::rich_location (line_maps */*set*/, source_location loc) : +rich_location::rich_location (line_maps *set, source_location loc) : + m_line_table (set), m_num_ranges (0), m_column_override (0), m_have_expanded_location (false), - m_num_fixit_hints (0) + m_num_fixit_hints (0), + m_seen_impossible_fixit (false) { add_range (loc, true); } @@ -2075,6 +2077,9 @@ void rich_location::add_fixit_insert (source_location where, const char *new_content) { + if (reject_impossible_fixit (where)) + return; + linemap_assert (m_num_fixit_hints < MAX_FIXIT_HINTS); m_fixit_hints[m_num_fixit_hints++] = new fixit_insert (where, new_content); @@ -2089,6 +2094,44 @@ rich_location::add_fixit_remove (source_range src_range) add_fixit_replace (src_range, ""); } +/* Return true iff A is in the column directly before B, on the + same line of the same source file. */ + +static bool +column_before_p (line_maps *set, source_location a, source_location b) +{ + if (IS_ADHOC_LOC (a)) + a = get_location_from_adhoc_loc (set, a); + if (IS_ADHOC_LOC (b)) + b = get_location_from_adhoc_loc (set, b); + + /* They must both be in ordinary maps. */ + const struct line_map *linemap_a = linemap_lookup (set, a); + if (linemap_macro_expansion_map_p (linemap_a)) + return false; + const struct line_map *linemap_b = linemap_lookup (set, b); + if (linemap_macro_expansion_map_p (linemap_b)) + return false; + + /* To be on the same line, they must be in the same ordinary map. */ + if (linemap_a != linemap_b) + return false; + + linenum_type line_a + = SOURCE_LINE (linemap_check_ordinary (linemap_a), a); + linenum_type line_b + = SOURCE_LINE (linemap_check_ordinary (linemap_b), b); + if (line_a != line_b) + return false; + + linenum_type column_a + = SOURCE_COLUMN (linemap_check_ordinary (linemap_a), a); + linenum_type column_b + = SOURCE_COLUMN (linemap_check_ordinary (linemap_b), b); + + return column_b == column_a + 1; +} + /* Add a fixit-hint, suggesting replacement of the content at SRC_RANGE with NEW_CONTENT. */ @@ -2097,10 +2140,67 @@ rich_location::add_fixit_replace (source_range src_range, const char *new_content) { linemap_assert (m_num_fixit_hints < MAX_FIXIT_HINTS); + + if (reject_impossible_fixit (src_range.m_start)) + return; + if (reject_impossible_fixit (src_range.m_finish)) + return; + + /* Consolidate neighboring fixits. */ + fixit_hint *prev = get_last_fixit_hint (); + if (m_num_fixit_hints > 0) + { + if (prev->maybe_append_replace (m_line_table, src_range, new_content)) + return; + } + m_fixit_hints[m_num_fixit_hints++] = new fixit_replace (src_range, new_content); } +/* Get the last fix-it hint within this rich_location, or NULL if none. */ + +fixit_hint * +rich_location::get_last_fixit_hint () const +{ + if (m_num_fixit_hints > 0) + return m_fixit_hints[m_num_fixit_hints - 1]; + else + return NULL; +} + +/* If WHERE is an "awkward" location, then mark this rich_location as not + supporting fixits, purging any thay were already added, and return true. + + Otherwise (the common case), return false. */ + +bool +rich_location::reject_impossible_fixit (source_location where) +{ + /* Fix-its within a rich_location should either all be suggested, or + none of them should be suggested. + Once we've rejected a fixit, we reject any more, even those + with reasonable locations. */ + if (m_seen_impossible_fixit) + return true; + + if (where <= LINE_MAP_MAX_LOCATION_WITH_COLS) + /* WHERE is a reasonable location for a fix-it; don't reject it. */ + return false; + + /* Otherwise we have an attempt to add a fix-it with an "awkward" + location: either one that we can't obtain column information + for (within an ordinary map), or one within a macro expansion. */ + m_seen_impossible_fixit = true; + + /* Purge the rich_location of any fix-its that were already added. */ + for (unsigned int i = 0; i < m_num_fixit_hints; i++) + delete m_fixit_hints[i]; + m_num_fixit_hints = 0; + + return true; +} + /* class fixit_insert. */ fixit_insert::fixit_insert (source_location where, @@ -2129,6 +2229,15 @@ fixit_insert::affects_line_p (const char *file, int line) return false; } +/* Implementation of maybe_append_replace for fixit_insert. Reject + the attempt to consolidate fix-its. */ + +bool +fixit_insert::maybe_append_replace (line_maps *, source_range, const char *) +{ + return false; +} + /* class fixit_replace. */ fixit_replace::fixit_replace (source_range src_range, @@ -2151,3 +2260,26 @@ fixit_replace::affects_line_p (const char *file, int line) { return m_src_range.intersects_line_p (file, line); } + +/* Implementation of maybe_append_replace for fixit_replace. If + possible, merge the new replacement into this one and return true. + Otherwise return false. */ + +bool +fixit_replace::maybe_append_replace (line_maps *set, + source_range src_range, + const char *new_content) +{ + /* Does SRC_RANGE start immediately after this one finishes? */ + if (!column_before_p (set, m_src_range.m_finish, src_range.m_start)) + return false; + + /* We have neighboring replacements; merge them. */ + m_src_range.m_finish = src_range.m_finish; + size_t extra_len = strlen (new_content); + m_bytes = (char *)xrealloc (m_bytes, m_len + extra_len + 1); + memcpy (m_bytes + m_len, new_content, extra_len); + m_len += extra_len; + m_bytes[m_len] = '\0'; + return true; +} -- cgit v1.1