diff options
| -rw-r--r-- | Documentation/gitattributes.txt | 34 | ||||
| -rw-r--r-- | Documentation/merge-config.txt | 10 | ||||
| -rw-r--r-- | builtin/merge.c | 3 | ||||
| -rw-r--r-- | cache.h | 2 | ||||
| -rw-r--r-- | convert.c | 16 | ||||
| -rw-r--r-- | environment.c | 1 | ||||
| -rw-r--r-- | ll-merge.c | 15 | ||||
| -rwxr-xr-x | t/t6038-merge-text-auto.sh | 64 |
8 files changed, 143 insertions, 2 deletions
diff --git a/Documentation/gitattributes.txt b/Documentation/gitattributes.txt index 564586b943..da553ff006 100644 --- a/Documentation/gitattributes.txt +++ b/Documentation/gitattributes.txt @@ -317,6 +317,17 @@ command is "cat"). smudge = cat ------------------------ +For best results, `clean` should not alter its output further if it is +run twice ("clean->clean" should be equivalent to "clean"), and +multiple `smudge` commands should not alter `clean`'s output +("smudge->smudge->clean" should be equivalent to "clean"). See the +section on merging below. + +The "indent" filter is well-behaved in this regard: it will not modify +input that is already correctly indented. In this case, the lack of a +smudge filter means that the clean filter _must_ accept its own output +without modifying it. + Interaction between checkin/checkout attributes ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ @@ -331,6 +342,29 @@ In the check-out codepath, the blob content is first converted with `text`, and then `ident` and fed to `filter`. +Merging branches with differing checkin/checkout attributes +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +If you have added attributes to a file that cause the canonical +repository format for that file to change, such as adding a +clean/smudge filter or text/eol/ident attributes, merging anything +where the attribute is not in place would normally cause merge +conflicts. + +To prevent these unnecessary merge conflicts, git can be told to run a +virtual check-out and check-in of all three stages of a file when +resolving a three-way merge by setting the `merge.renormalize` +configuration variable. This prevents changes caused by check-in +conversion from causing spurious merge conflicts when a converted file +is merged with an unconverted file. + +As long as a "smudge->clean" results in the same output as a "clean" +even on files that are already smudged, this strategy will +automatically resolve all filter-related conflicts. Filters that do +not act in this way may cause additional merge conflicts that must be +resolved manually. + + Generating diff text ~~~~~~~~~~~~~~~~~~~~ diff --git a/Documentation/merge-config.txt b/Documentation/merge-config.txt index a403155052..b72f533970 100644 --- a/Documentation/merge-config.txt +++ b/Documentation/merge-config.txt @@ -15,6 +15,16 @@ merge.renameLimit:: during a merge; if not specified, defaults to the value of diff.renameLimit. +merge.renormalize:: + Tell git that canonical representation of files in the + repository has changed over time (e.g. earlier commits record + text files with CRLF line endings, but recent ones use LF line + endings). In such a repository, git can convert the data + recorded in commits to a canonical form before performing a + merge to reduce unnecessary conflicts. For more information, + see section "Merging branches with differing checkin/checkout + attributes" in linkgit:gitattributes[5]. + merge.stat:: Whether to print the diffstat between ORIG_HEAD and the merge result at the end of the merge. True by default. diff --git a/builtin/merge.c b/builtin/merge.c index 37ce4f589f..b836e9c68b 100644 --- a/builtin/merge.c +++ b/builtin/merge.c @@ -503,6 +503,9 @@ static int git_merge_config(const char *k, const char *v, void *cb) return git_config_string(&pull_octopus, k, v); else if (!strcmp(k, "merge.log") || !strcmp(k, "merge.summary")) option_log = git_config_bool(k, v); + else if (!strcmp(k, "merge.renormalize")) { + merge_renormalize = git_config_bool(k, v); + } return git_diff_ui_config(k, v, cb); } @@ -551,6 +551,7 @@ extern int read_replace_refs; extern int fsync_object_files; extern int core_preload_index; extern int core_apply_sparse_checkout; +extern int merge_renormalize; enum safe_crlf { SAFE_CRLF_FALSE = 0, @@ -1054,6 +1055,7 @@ extern void trace_argv_printf(const char **argv, const char *format, ...); extern int convert_to_git(const char *path, const char *src, size_t len, struct strbuf *dst, enum safe_crlf checksafe); extern int convert_to_working_tree(const char *path, const char *src, size_t len, struct strbuf *dst); +extern int renormalize_buffer(const char *path, const char *src, size_t len, struct strbuf *dst); /* add */ /* @@ -93,7 +93,8 @@ static int is_binary(unsigned long size, struct text_stat *stats) return 0; } -static enum eol determine_output_conversion(enum action action) { +static enum eol determine_output_conversion(enum action action) +{ switch (action) { case CRLF_BINARY: return EOL_UNSET; @@ -693,7 +694,8 @@ static int git_path_check_ident(const char *path, struct git_attr_check *check) return !!ATTR_TRUE(value); } -enum action determine_action(enum action text_attr, enum eol eol_attr) { +static enum action determine_action(enum action text_attr, enum eol eol_attr) +{ if (text_attr == CRLF_BINARY) return CRLF_BINARY; if (eol_attr == EOL_LF) @@ -773,3 +775,13 @@ int convert_to_working_tree(const char *path, const char *src, size_t len, struc } return ret | apply_filter(path, src, len, dst, filter); } + +int renormalize_buffer(const char *path, const char *src, size_t len, struct strbuf *dst) +{ + int ret = convert_to_working_tree(path, src, len, dst); + if (ret) { + src = dst->buf; + len = dst->len; + } + return ret | convert_to_git(path, src, len, dst, 0); +} diff --git a/environment.c b/environment.c index 83d38d3c23..81a36824f0 100644 --- a/environment.c +++ b/environment.c @@ -53,6 +53,7 @@ enum object_creation_mode object_creation_mode = OBJECT_CREATION_MODE; char *notes_ref_name; int grafts_replace_parents = 1; int core_apply_sparse_checkout; +int merge_renormalize; /* Parallel index stat data preload? */ int core_preload_index = 0; diff --git a/ll-merge.c b/ll-merge.c index 3764a1ab72..5068fe069f 100644 --- a/ll-merge.c +++ b/ll-merge.c @@ -321,6 +321,16 @@ static int git_path_check_merge(const char *path, struct git_attr_check check[2] return git_checkattr(path, 2, check); } +static void normalize_file(mmfile_t *mm, const char *path) +{ + struct strbuf strbuf = STRBUF_INIT; + if (renormalize_buffer(path, mm->ptr, mm->size, &strbuf)) { + free(mm->ptr); + mm->size = strbuf.len; + mm->ptr = strbuf_detach(&strbuf, NULL); + } +} + int ll_merge(mmbuffer_t *result_buf, const char *path, mmfile_t *ancestor, const char *ancestor_label, @@ -334,6 +344,11 @@ int ll_merge(mmbuffer_t *result_buf, const struct ll_merge_driver *driver; int virtual_ancestor = flag & 01; + if (merge_renormalize) { + normalize_file(ancestor, path); + normalize_file(ours, path); + normalize_file(theirs, path); + } if (!git_path_check_merge(path, check)) { ll_driver_name = check[0].value; if (check[1].value) { diff --git a/t/t6038-merge-text-auto.sh b/t/t6038-merge-text-auto.sh new file mode 100755 index 0000000000..127baf8560 --- /dev/null +++ b/t/t6038-merge-text-auto.sh @@ -0,0 +1,64 @@ +#!/bin/sh + +test_description='CRLF merge conflict across text=auto change' + +. ./test-lib.sh + +test_expect_success setup ' + git config merge.renormalize true && + git config core.autocrlf false && + echo first line | append_cr >file && + echo first line >control_file && + echo only line >inert_file && + git add file control_file inert_file && + git commit -m "Initial" && + git tag initial && + git branch side && + echo "* text=auto" >.gitattributes && + touch file && + git add .gitattributes file && + git commit -m "normalize file" && + echo same line | append_cr >>file && + echo same line >>control_file && + git add file control_file && + git commit -m "add line from a" && + git tag a && + git rm .gitattributes && + rm file && + git checkout file && + git commit -m "remove .gitattributes" && + git tag c && + git checkout side && + echo same line | append_cr >>file && + echo same line >>control_file && + git add file control_file && + git commit -m "add line from b" && + git tag b && + git checkout master +' + +test_expect_success 'Check merging after setting text=auto' ' + git reset --hard a && + git merge b && + cat file | remove_cr >file.temp && + test_cmp file file.temp +' + +test_expect_success 'Check merging addition of text=auto' ' + git reset --hard b && + git merge a && + cat file | remove_cr >file.temp && + test_cmp file file.temp +' + +test_expect_failure 'Test delete/normalize conflict' ' + git checkout side && + git reset --hard initial && + git rm file && + git commit -m "remove file" && + git checkout master && + git reset --hard a^ && + git merge side +' + +test_done |