From 6612b9e471a3e25079dac5257ead8cf6abe68575 Mon Sep 17 00:00:00 2001 From: Erik Faye-Lund Date: Fri, 26 Nov 2010 17:00:39 +0100 Subject: [PATCH] help: always suggest common-cmds if prefix of cmd If someone runs "git st", the command "git status" is not suggested because it's not one of the closest levenshtein-neighbour. Reserve the distance of 0 for common commands where the entered command is a prefixe, as these are often more likely to be what the user meant. This way, "git status" is the first suggestion, while a list of possible typos are still suggested as well. Signed-off-by: Erik Faye-Lund Signed-off-by: Junio C Hamano --- Makefile | 2 ++ help.c | 47 +++++++++++++++++++++++++++++++++++++++-------- 2 files changed, 41 insertions(+), 8 deletions(-) diff --git a/Makefile b/Makefile index 919ed2b7e..7baa621c1 100644 --- a/Makefile +++ b/Makefile @@ -1620,6 +1620,8 @@ git$X: git.o $(BUILTIN_OBJS) $(GITLIBS) $(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ git.o \ $(BUILTIN_OBJS) $(ALL_LDFLAGS) $(LIBS) +help.o: common-cmds.h + builtin/help.o: common-cmds.h builtin/help.s builtin/help.o: EXTRA_CPPFLAGS = \ '-DGIT_HTML_PATH="$(htmldir_SQ)"' \ diff --git a/help.c b/help.c index 7f4928e45..7654f1bfd 100644 --- a/help.c +++ b/help.c @@ -3,6 +3,7 @@ #include "exec_cmd.h" #include "levenshtein.h" #include "help.h" +#include "common-cmds.h" /* most GUI terminals set COLUMNS (although some don't export it) */ static int term_columns(void) @@ -298,7 +299,8 @@ static void add_cmd_list(struct cmdnames *cmds, struct cmdnames *old) } /* An empirically derived magic number */ -#define SIMILAR_ENOUGH(x) ((x) < 6) +#define SIMILARITY_FLOOR 7 +#define SIMILAR_ENOUGH(x) ((x) < SIMILARITY_FLOOR) const char *help_unknown_cmd(const char *cmd) { @@ -319,10 +321,28 @@ const char *help_unknown_cmd(const char *cmd) sizeof(main_cmds.names), cmdname_compare); uniq(&main_cmds); - /* This reuses cmdname->len for similarity index */ - for (i = 0; i < main_cmds.cnt; ++i) + /* This abuses cmdname->len for levenshtein distance */ + for (i = 0, n = 0; i < main_cmds.cnt; i++) { + int cmp = 0; /* avoid compiler stupidity */ + const char *candidate = main_cmds.names[i]->name; + + /* Does the candidate appear in common_cmds list? */ + while (n < ARRAY_SIZE(common_cmds) && + (cmp = strcmp(common_cmds[n].name, candidate)) < 0) + n++; + if ((n < ARRAY_SIZE(common_cmds)) && !cmp) { + /* Yes, this is one of the common commands */ + n++; /* use the entry from common_cmds[] */ + if (!prefixcmp(candidate, cmd)) { + /* Give prefix match a very good score */ + main_cmds.names[i]->len = 0; + continue; + } + } + main_cmds.names[i]->len = - levenshtein(cmd, main_cmds.names[i]->name, 0, 2, 1, 4); + levenshtein(cmd, candidate, 0, 2, 1, 4) + 1; + } qsort(main_cmds.names, main_cmds.cnt, sizeof(*main_cmds.names), levenshtein_compare); @@ -330,10 +350,21 @@ const char *help_unknown_cmd(const char *cmd) if (!main_cmds.cnt) die ("Uh oh. Your system reports no Git commands at all."); - best_similarity = main_cmds.names[0]->len; - n = 1; - while (n < main_cmds.cnt && best_similarity == main_cmds.names[n]->len) - ++n; + /* skip and count prefix matches */ + for (n = 0; n < main_cmds.cnt && !main_cmds.names[n]->len; n++) + ; /* still counting */ + + if (main_cmds.cnt <= n) { + /* prefix matches with everything? that is too ambiguous */ + best_similarity = SIMILARITY_FLOOR + 1; + } else { + /* count all the most similar ones */ + for (best_similarity = main_cmds.names[n++]->len; + (n < main_cmds.cnt && + best_similarity == main_cmds.names[n]->len); + n++) + ; /* still counting */ + } if (autocorrect && n == 1 && SIMILAR_ENOUGH(best_similarity)) { const char *assumed = main_cmds.names[0]->name; main_cmds.names[0] = NULL; -- 2.30.2