From 23b65f9528a1fa19619d1dcb59932cc55075808c Mon Sep 17 00:00:00 2001 From: Jonathan Tan Date: Fri, 11 Aug 2017 15:49:14 -0700 Subject: diff: avoid redundantly clearing a flag No code in diff.c sets DIFF_SYMBOL_MOVED_LINE except in mark_color_as_moved(), so it is redundant to clear it for the current line. Therefore, clear it only for previous lines. This makes a refactoring in a subsequent patch easier. Signed-off-by: Jonathan Tan Signed-off-by: Junio C Hamano diff --git a/diff.c b/diff.c index 4af73a7..23311f9 100644 --- a/diff.c +++ b/diff.c @@ -898,7 +898,7 @@ static void mark_color_as_moved(struct diff_options *o, if (!match) { if (block_length < COLOR_MOVED_MIN_BLOCK_LENGTH && o->color_moved != COLOR_MOVED_PLAIN) { - for (i = 0; i < block_length + 1; i++) { + for (i = 1; i < block_length + 1; i++) { l = &o->emitted_symbols->buf[n - i]; l->flags &= ~DIFF_SYMBOL_MOVED_LINE; } -- cgit v0.10.2-6-g49f6 From 09153277f8948d3ed8cb6712f135a9caeaa006f6 Mon Sep 17 00:00:00 2001 From: Jonathan Tan Date: Tue, 15 Aug 2017 18:27:38 -0700 Subject: diff: respect MIN_BLOCK_LENGTH for last block Currently, MIN_BLOCK_LENGTH is only checked when diff encounters a line that does not belong to the current block. In particular, this means that MIN_BLOCK_LENGTH is not checked after all lines are encountered. Perform that check. Signed-off-by: Jonathan Tan Signed-off-by: Junio C Hamano diff --git a/diff.c b/diff.c index 23311f9..f598d8a 100644 --- a/diff.c +++ b/diff.c @@ -861,6 +861,26 @@ static int shrink_potential_moved_blocks(struct moved_entry **pmb, return rp + 1; } +/* + * If o->color_moved is COLOR_MOVED_PLAIN, this function does nothing. + * + * Otherwise, if the last block has fewer lines than + * COLOR_MOVED_MIN_BLOCK_LENGTH, unset DIFF_SYMBOL_MOVED_LINE on all lines in + * that block. + * + * The last block consists of the (n - block_length)'th line up to but not + * including the nth line. + */ +static void adjust_last_block(struct diff_options *o, int n, int block_length) +{ + int i; + if (block_length >= COLOR_MOVED_MIN_BLOCK_LENGTH || + o->color_moved == COLOR_MOVED_PLAIN) + return; + for (i = 1; i < block_length + 1; i++) + o->emitted_symbols->buf[n - i].flags &= ~DIFF_SYMBOL_MOVED_LINE; +} + /* Find blocks of moved code, delegate actual coloring decision to helper */ static void mark_color_as_moved(struct diff_options *o, struct hashmap *add_lines, @@ -896,13 +916,7 @@ static void mark_color_as_moved(struct diff_options *o, } if (!match) { - if (block_length < COLOR_MOVED_MIN_BLOCK_LENGTH && - o->color_moved != COLOR_MOVED_PLAIN) { - for (i = 1; i < block_length + 1; i++) { - l = &o->emitted_symbols->buf[n - i]; - l->flags &= ~DIFF_SYMBOL_MOVED_LINE; - } - } + adjust_last_block(o, n, block_length); pmb_nr = 0; block_length = 0; continue; @@ -944,6 +958,7 @@ static void mark_color_as_moved(struct diff_options *o, if (flipped_block) l->flags |= DIFF_SYMBOL_MOVED_LINE_ALT; } + adjust_last_block(o, n, block_length); free(pmb); } diff --git a/t/t4015-diff-whitespace.sh b/t/t4015-diff-whitespace.sh index c3b6974..6ae62a6 100755 --- a/t/t4015-diff-whitespace.sh +++ b/t/t4015-diff-whitespace.sh @@ -1382,6 +1382,43 @@ EOF test_cmp expected actual ' +test_expect_success '--color-moved block at end of diff output respects MIN_BLOCK_LENGTH' ' + git reset --hard && + >bar && + cat <<-\EOF >foo && + irrelevant_line + line1 + EOF + git add foo bar && + git commit -m x && + + cat <<-\EOF >bar && + line1 + EOF + cat <<-\EOF >foo && + irrelevant_line + EOF + + git diff HEAD --color-moved=zebra --no-renames | + grep -v "index" | + test_decode_color >actual && + cat >expected <<-\EOF && + diff --git a/bar b/bar + --- a/bar + +++ b/bar + @@ -0,0 +1 @@ + +line1 + diff --git a/foo b/foo + --- a/foo + +++ b/foo + @@ -1,2 +1 @@ + irrelevant_line + -line1 + EOF + + test_cmp expected actual +' + test_expect_success 'move detection with submodules' ' test_create_repo bananas && echo ripe >bananas/recipe && -- cgit v0.10.2-6-g49f6 From f0b8fb6e591b50b72b921f2c4cf120ebd284f510 Mon Sep 17 00:00:00 2001 From: Jonathan Tan Date: Tue, 15 Aug 2017 18:27:39 -0700 Subject: diff: define block by number of alphanumeric chars The existing behavior of diff --color-moved=zebra does not define the minimum size of a block at all, instead relying on a heuristic applied later to filter out sets of adjacent moved lines that are shorter than 3 lines long. This can be confusing, because a block could thus be colored as moved at the source but not at the destination (or vice versa), depending on its neighbors. Instead, teach diff that the minimum size of a block is 20 alphanumeric characters, the same heuristic used by "git blame". This allows diff to still exclude uninteresting lines appearing on their own (such as those solely consisting of one or a few closing braces), as was the intention of the adjacent-moved-line heuristic. This requires a change in some tests in that some of their lines are no longer considered to be part of a block, because they are too short. Signed-off-by: Jonathan Tan Signed-off-by: Junio C Hamano diff --git a/Documentation/diff-options.txt b/Documentation/diff-options.txt index bc52bd0..b8c8816 100644 --- a/Documentation/diff-options.txt +++ b/Documentation/diff-options.txt @@ -254,13 +254,11 @@ plain:: moved line, but it is not very useful in a review to determine if a block of code was moved without permutation. zebra:: - Blocks of moved code are detected greedily. The detected blocks are + Blocks of moved text of at least 20 alphanumeric characters + are detected greedily. The detected blocks are painted using either the 'color.diff.{old,new}Moved' color or 'color.diff.{old,new}MovedAlternative'. The change between - the two colors indicates that a new block was detected. If there - are fewer than 3 adjacent moved lines, they are not marked up - as moved, but the regular colors 'color.diff.{old,new}' will be - used. + the two colors indicates that a new block was detected. dimmed_zebra:: Similar to 'zebra', but additional dimming of uninteresting parts of moved code is performed. The bordering lines of two adjacent diff --git a/diff.c b/diff.c index f598d8a..c50fcc7 100644 --- a/diff.c +++ b/diff.c @@ -864,19 +864,31 @@ static int shrink_potential_moved_blocks(struct moved_entry **pmb, /* * If o->color_moved is COLOR_MOVED_PLAIN, this function does nothing. * - * Otherwise, if the last block has fewer lines than - * COLOR_MOVED_MIN_BLOCK_LENGTH, unset DIFF_SYMBOL_MOVED_LINE on all lines in + * Otherwise, if the last block has fewer alphanumeric characters than + * COLOR_MOVED_MIN_ALNUM_COUNT, unset DIFF_SYMBOL_MOVED_LINE on all lines in * that block. * * The last block consists of the (n - block_length)'th line up to but not * including the nth line. + * + * NEEDSWORK: This uses the same heuristic as blame_entry_score() in blame.c. + * Think of a way to unify them. */ static void adjust_last_block(struct diff_options *o, int n, int block_length) { - int i; - if (block_length >= COLOR_MOVED_MIN_BLOCK_LENGTH || - o->color_moved == COLOR_MOVED_PLAIN) + int i, alnum_count = 0; + if (o->color_moved == COLOR_MOVED_PLAIN) return; + for (i = 1; i < block_length + 1; i++) { + const char *c = o->emitted_symbols->buf[n - i].line; + for (; *c; c++) { + if (!isalnum(*c)) + continue; + alnum_count++; + if (alnum_count >= COLOR_MOVED_MIN_ALNUM_COUNT) + return; + } + } for (i = 1; i < block_length + 1; i++) o->emitted_symbols->buf[n - i].flags &= ~DIFF_SYMBOL_MOVED_LINE; } @@ -923,7 +935,6 @@ static void mark_color_as_moved(struct diff_options *o, } l->flags |= DIFF_SYMBOL_MOVED_LINE; - block_length++; if (o->color_moved == COLOR_MOVED_PLAIN) continue; @@ -953,8 +964,13 @@ static void mark_color_as_moved(struct diff_options *o, } flipped_block = (flipped_block + 1) % 2; + + adjust_last_block(o, n, block_length); + block_length = 0; } + block_length++; + if (flipped_block) l->flags |= DIFF_SYMBOL_MOVED_LINE_ALT; } diff --git a/diff.h b/diff.h index 5755f46..aca150b 100644 --- a/diff.h +++ b/diff.h @@ -195,7 +195,7 @@ struct diff_options { COLOR_MOVED_ZEBRA_DIM = 3, } color_moved; #define COLOR_MOVED_DEFAULT COLOR_MOVED_ZEBRA - #define COLOR_MOVED_MIN_BLOCK_LENGTH 3 + #define COLOR_MOVED_MIN_ALNUM_COUNT 20 }; void diff_emit_submodule_del(struct diff_options *o, const char *line); diff --git a/t/t4015-diff-whitespace.sh b/t/t4015-diff-whitespace.sh index 6ae62a6..12d182d 100755 --- a/t/t4015-diff-whitespace.sh +++ b/t/t4015-diff-whitespace.sh @@ -1101,9 +1101,9 @@ test_expect_success 'detect malicious moved code, inside file' ' -{ -if (!u->is_allowed_foo) -return; - -foo(u); - -} - - + -foo(u); + -} + - int main() { foo(); @@ -1117,11 +1117,11 @@ test_expect_success 'detect malicious moved code, inside file' ' +int secure_foo(struct user *u) +{ - +foo(u); + +foo(u); +if (!u->is_allowed_foo) +return; - +} - + + +} + + int another_function() { bar(); @@ -1182,9 +1182,9 @@ test_expect_success 'plain moved code, inside file' ' test_expect_success 'detect permutations inside moved code -- dimmed_zebra' ' git reset --hard && cat <<-\EOF >lines.txt && - line 1 - line 2 - line 3 + long line 1 + long line 2 + long line 3 line 4 line 5 line 6 @@ -1195,9 +1195,9 @@ test_expect_success 'detect permutations inside moved code -- dimmed_zebra' ' line 11 line 12 line 13 - line 14 - line 15 - line 16 + long line 14 + long line 15 + long line 16 EOF git add lines.txt && git commit -m "add poetry" && @@ -1208,12 +1208,12 @@ test_expect_success 'detect permutations inside moved code -- dimmed_zebra' ' line 7 line 8 line 9 - line 1 - line 2 - line 3 - line 14 - line 15 - line 16 + long line 1 + long line 2 + long line 3 + long line 14 + long line 15 + long line 16 line 10 line 11 line 12 @@ -1227,35 +1227,36 @@ test_expect_success 'detect permutations inside moved code -- dimmed_zebra' ' test_config color.diff.newMovedDimmed "normal cyan" && test_config color.diff.oldMovedAlternativeDimmed "normal blue" && test_config color.diff.newMovedAlternativeDimmed "normal yellow" && - git diff HEAD --no-renames --color-moved=dimmed_zebra| test_decode_color >actual && + git diff HEAD --no-renames --color-moved=dimmed_zebra | + grep -v "index" | + test_decode_color >actual && cat <<-\EOF >expected && diff --git a/lines.txt b/lines.txt - index 47ea9c3..ba96a38 100644 --- a/lines.txt +++ b/lines.txt @@ -1,16 +1,16 @@ - -line 1 - -line 2 - -line 3 + -long line 1 + -long line 2 + -long line 3 line 4 line 5 line 6 line 7 line 8 line 9 - +line 1 - +line 2 - +line 3 - +line 14 - +line 15 - +line 16 + +long line 1 + +long line 2 + +long line 3 + +long line 14 + +long line 15 + +long line 16 line 10 line 11 line 12 line 13 - -line 14 - -line 15 - -line 16 + -long line 14 + -long line 15 + -long line 16 EOF test_cmp expected actual ' @@ -1270,35 +1271,36 @@ test_expect_success 'cmd option assumes configured colored-moved' ' test_config color.diff.oldMovedAlternativeDimmed "normal blue" && test_config color.diff.newMovedAlternativeDimmed "normal yellow" && test_config diff.colorMoved zebra && - git diff HEAD --no-renames --color-moved| test_decode_color >actual && + git diff HEAD --no-renames --color-moved | + grep -v "index" | + test_decode_color >actual && cat <<-\EOF >expected && diff --git a/lines.txt b/lines.txt - index 47ea9c3..ba96a38 100644 --- a/lines.txt +++ b/lines.txt @@ -1,16 +1,16 @@ - -line 1 - -line 2 - -line 3 + -long line 1 + -long line 2 + -long line 3 line 4 line 5 line 6 line 7 line 8 line 9 - +line 1 - +line 2 - +line 3 - +line 14 - +line 15 - +line 16 + +long line 1 + +long line 2 + +long line 3 + +long line 14 + +long line 15 + +long line 16 line 10 line 11 line 12 line 13 - -line 14 - -line 15 - -line 16 + -long line 14 + -long line 15 + -long line 16 EOF test_cmp expected actual ' @@ -1324,16 +1326,16 @@ line 1 line 2 line 3 line 4 -line 5 -line 6 -line 7 +long line 5 +long line 6 +long line 7 EOF git add lines.txt && git commit -m "add poetry" && cat <<\EOF >lines.txt && - line 5 - line 6 - line 7 + long line 5 + long line 6 + long line 7 line 1 line 2 line 3 @@ -1341,48 +1343,50 @@ line 4 EOF test_config color.diff.oldMoved "magenta" && test_config color.diff.newMoved "cyan" && - git diff HEAD --no-renames --color-moved| test_decode_color >actual && + git diff HEAD --no-renames --color-moved | + grep -v "index" | + test_decode_color >actual && cat <<-\EOF >expected && diff --git a/lines.txt b/lines.txt - index 734156d..eb89ead 100644 --- a/lines.txt +++ b/lines.txt @@ -1,7 +1,7 @@ - + line 5 - + line 6 - + line 7 + + long line 5 + + long line 6 + + long line 7 line 1 line 2 line 3 line 4 - -line 5 - -line 6 - -line 7 + -long line 5 + -long line 6 + -long line 7 EOF test_cmp expected actual && - git diff HEAD --no-renames -w --color-moved| test_decode_color >actual && + git diff HEAD --no-renames -w --color-moved | + grep -v "index" | + test_decode_color >actual && cat <<-\EOF >expected && diff --git a/lines.txt b/lines.txt - index 734156d..eb89ead 100644 --- a/lines.txt +++ b/lines.txt @@ -1,7 +1,7 @@ - + line 5 - + line 6 - + line 7 + + long line 5 + + long line 6 + + long line 7 line 1 line 2 line 3 line 4 - -line 5 - -line 6 - -line 7 + -long line 5 + -long line 6 + -long line 7 EOF test_cmp expected actual ' -test_expect_success '--color-moved block at end of diff output respects MIN_BLOCK_LENGTH' ' +test_expect_success '--color-moved block at end of diff output respects MIN_ALNUM_COUNT' ' git reset --hard && >bar && cat <<-\EOF >foo && @@ -1419,6 +1423,90 @@ test_expect_success '--color-moved block at end of diff output respects MIN_BLOC test_cmp expected actual ' +test_expect_success '--color-moved respects MIN_ALNUM_COUNT' ' + git reset --hard && + cat <<-\EOF >foo && + nineteen chars 456789 + irrelevant_line + twenty chars 234567890 + EOF + >bar && + git add foo bar && + git commit -m x && + + cat <<-\EOF >foo && + irrelevant_line + EOF + cat <<-\EOF >bar && + twenty chars 234567890 + nineteen chars 456789 + EOF + + git diff HEAD --color-moved=zebra --no-renames | + grep -v "index" | + test_decode_color >actual && + cat >expected <<-\EOF && + diff --git a/bar b/bar + --- a/bar + +++ b/bar + @@ -0,0 +1,2 @@ + +twenty chars 234567890 + +nineteen chars 456789 + diff --git a/foo b/foo + --- a/foo + +++ b/foo + @@ -1,3 +1 @@ + -nineteen chars 456789 + irrelevant_line + -twenty chars 234567890 + EOF + + test_cmp expected actual +' + +test_expect_success '--color-moved treats adjacent blocks as separate for MIN_ALNUM_COUNT' ' + git reset --hard && + cat <<-\EOF >foo && + 7charsA + irrelevant_line + 7charsB + 7charsC + EOF + >bar && + git add foo bar && + git commit -m x && + + cat <<-\EOF >foo && + irrelevant_line + EOF + cat <<-\EOF >bar && + 7charsB + 7charsC + 7charsA + EOF + + git diff HEAD --color-moved=zebra --no-renames | grep -v "index" | test_decode_color >actual && + cat >expected <<-\EOF && + diff --git a/bar b/bar + --- a/bar + +++ b/bar + @@ -0,0 +1,3 @@ + +7charsB + +7charsC + +7charsA + diff --git a/foo b/foo + --- a/foo + +++ b/foo + @@ -1,4 +1 @@ + -7charsA + irrelevant_line + -7charsB + -7charsC + EOF + + test_cmp expected actual +' + test_expect_success 'move detection with submodules' ' test_create_repo bananas && echo ripe >bananas/recipe && -- cgit v0.10.2-6-g49f6