diff options
| -rw-r--r-- | editors/diff.c | 94 | ||||
| -rwxr-xr-x | testsuite/diff.tests | 31 |
2 files changed, 71 insertions, 54 deletions
diff --git a/editors/diff.c b/editors/diff.c index 2e3a455..e4d74ab 100644 --- a/editors/diff.c +++ b/editors/diff.c @@ -368,16 +368,6 @@ static int line_compar(const void *a, const void *b) #undef l1 } -static void uni_range(int a, int b) -{ - if (a < b) - printf("%d,%d", a, b - a + 1); - else if (a == b) - printf("%d", b); - else - printf("%d,0", b); -} - static void fetch(FILE_and_pos_t *ft, const off_t *ix, int a, int b, int ch) { for (int i = a; i <= b; i++) { @@ -561,17 +551,6 @@ start: return J; } -/* - * The following struct is used to record change information - * doing a "context" or "unified" diff. - */ -struct context_vec { - int a; /* start line in old file */ - int b; /* end line in old file */ - int c; /* start line in new file */ - int d; /* end line in new file */ -}; - static bool diff(FILE* fp[2], char *file[2]) { int nlen[2]; @@ -580,22 +559,23 @@ static bool diff(FILE* fp[2], char *file[2]) int *J = create_J(ft, nlen, ix); bool anychange = false; - struct context_vec *vec = NULL; - int idx = -1, i = 1; + typedef struct { int a, b; } vec_t[2]; + vec_t *vec = NULL; + int i = 1, idx = -1; do { bool nonempty = false; while (1) { - struct context_vec v; + vec_t v; - for (v.a = i; v.a <= nlen[0] && J[v.a] == J[v.a - 1] + 1; v.a++) + for (v[0].a = i; v[0].a <= nlen[0] && J[v[0].a] == J[v[0].a - 1] + 1; v[0].a++) continue; - v.c = J[v.a - 1] + 1; + v[1].a = J[v[0].a - 1] + 1; - for (v.b = v.a - 1; v.b < nlen[0] && !J[v.b + 1]; v.b++) + for (v[0].b = v[0].a - 1; v[0].b < nlen[0] && !J[v[0].b + 1]; v[0].b++) continue; - v.d = J[v.b + 1] - 1; + v[1].b = J[v[0].b + 1] - 1; /* * Indicate that there is a difference between lines a and b of the 'from' file * to get to lines c to d of the 'to' file. If a is greater than b then there @@ -603,35 +583,36 @@ static bool diff(FILE* fp[2], char *file[2]) * lines appended (beginning at b). If c is greater than d then there are * lines missing from the 'to' file. */ - if (v.a <= v.b || v.c <= v.d) { + if (v[0].a <= v[0].b || v[1].a <= v[1].b) { /* * If this change is more than 'context' lines from the * previous change, dump the record and reset it. */ + int ct = (2 * opt_U_context) + 1; if (idx >= 0 - && v.a > vec[idx].b + (2 * opt_U_context) + 1 - && v.c > vec[idx].d + (2 * opt_U_context) + 1 + && v[0].a > vec[idx][0].b + ct + && v[1].a > vec[idx][1].b + ct ) { break; } - nonempty |= (v.a >= v.b) && (v.c >= v.d); + + for (int j = 0; j < 2; j++) + for (int k = v[j].a; k < v[j].b; k++) + nonempty |= (ix[j][k+1] - ix[j][k] != 1); + vec = xrealloc_vector(vec, 6, ++idx); - vec[idx] = v; + memcpy(vec[idx], v, sizeof(v)); } - i = v.b + 1; + i = v[0].b + 1; if (i > nlen[0]) break; - J[v.b] = v.d; + J[v[0].b] = v[1].b; } - if (idx < 0) - continue; - if (!(option_mask32 & (FLAG(q)+FLAG(B))) && !nonempty) { - struct context_vec *cvp = vec; - int lowa = MAX(1, cvp->a - opt_U_context); - int upb = MIN(nlen[0], vec[idx].b + opt_U_context); - int lowc = MAX(1, cvp->c - opt_U_context); - int upd = MIN(nlen[1], vec[idx].d + opt_U_context); + if (idx < 0 || ((option_mask32 & FLAG(B)) && !nonempty)) + goto cont; + if (!(option_mask32 & FLAG(q))) { + vec_t span, *cvp = vec; if (!anychange) { /* Print the context/unidiff header first time through */ @@ -639,28 +620,33 @@ static bool diff(FILE* fp[2], char *file[2]) printf("+++ %s\n", label[1] ? label[1] : file[1]); } - printf("@@ -"); - uni_range(lowa, upb); - printf(" +"); - uni_range(lowc, upd); - printf(" @@\n"); + printf("@@"); + for (int j = 0; j < 2; j++) { + int a = span[j].a = MAX(1, (*cvp)[j].a - opt_U_context); + int b = span[j].b = MIN(nlen[j], vec[idx][j].b + opt_U_context); + printf(" %c%d", j ? '+' : '-', MIN(a, b)); + if (a == b) + continue; + printf(",%d", (a < b) ? b - a + 1 : 0); + } + printf(" @@\n"); /* * Output changes in "unified" diff format--the old and new lines * are printed together. */ - while (1) { + for (int lowa = span[0].a; ; lowa = (*cvp++)[0].b + 1) { bool end = cvp > &vec[idx]; - fetch(&ft[0], ix[0], lowa, end ? upb : cvp->a - 1, ' '); + fetch(&ft[0], ix[0], lowa, end ? span[0].b : (*cvp)[0].a - 1, ' '); if (end) break; - fetch(&ft[0], ix[0], cvp->a, cvp->b, '-'); - fetch(&ft[1], ix[1], cvp->c, cvp->d, '+'); - lowa = cvp++->b + 1; + for (int j = 0; j < 2; j++) + fetch(&ft[j], ix[j], (*cvp)[j].a, (*cvp)[j].b, j ? '+' : '-'); } } - idx = -1; anychange = true; + cont: + idx = -1; } while (i <= nlen[0]); free(vec); diff --git a/testsuite/diff.tests b/testsuite/diff.tests index f7bde2f..72ebb6c 100755 --- a/testsuite/diff.tests +++ b/testsuite/diff.tests @@ -44,6 +44,17 @@ testing "diff of stdin, twice" \ "" \ "stdin" +testing "diff of empty file against nonempty one" \ + "diff -u - input | $TRIM_TAB" \ +"\ +--- - ++++ input +@@ -0,0 +1 @@ ++a +" \ + "a\n" \ + "" + testing "diff -b treats EOF as whitespace" \ 'diff -ub - input; echo $?' \ "0\n" \ @@ -56,6 +67,26 @@ testing "diff -b treats all spaces as equal" \ "a \t c\n" \ "a\t \tc\n" +testing "diff -B ignores changes whose lines are all blank" \ + 'diff -uB - input; echo $?' \ + "0\n" \ + "a\n" \ + "\na\n\n" + +testing "diff -B does not ignore changes whose lines are not all blank" \ + "diff -uB - input | $TRIM_TAB" \ +"\ +--- - ++++ input +@@ -1,3 +1 @@ +- +-b +- ++a +" \ + "a\n" \ + "\nb\n\n" + testing "diff always takes context from old file" \ "diff -ub - input | $TRIM_TAB" \ "\ |