From: Karthik Nayak <karthik.188@xxxxxxxxx>
Implement %(if), %(then) and %(else) atoms. Used as
%(if)...%(then)...%(end) or %(if)...%(then)...%(else)...%(end). If the
format string between %(if) and %(then) expands to an empty string, or
to only whitespaces, then the whole %(if)...%(end) expands to the string
following %(then). Otherwise, it expands to the string following
%(else), if any. Nesting of this construct is possible.
This is in preparation for porting over `git branch -l` to use
ref-filter APIs for printing.
Add Documentation and tests regarding the same.
Mentored-by: Christian Couder <christian.couder@xxxxxxxxx>
Mentored-by: Matthieu Moy <matthieu.moy@xxxxxxxxxxxxxxx>
Signed-off-by: Karthik Nayak <karthik.188@xxxxxxxxx>
---
Documentation/git-for-each-ref.txt | 34 ++++++++++
ref-filter.c | 134 +++++++++++++++++++++++++++++++++++--
t/t6302-for-each-ref-filter.sh | 76 +++++++++++++++++++++
3 files changed, 237 insertions(+), 7 deletions(-)
diff --git a/Documentation/git-for-each-ref.txt b/Documentation/git-for-each-ref.txt
index f57e69b..3018969 100644
--- a/Documentation/git-for-each-ref.txt
+++ b/Documentation/git-for-each-ref.txt
@@ -146,6 +146,16 @@ align::
quoted, but if nested then only the topmost level performs
quoting.
+if::
+ Used as %(if)...%(then)...%(end) or
+ %(if)...%(then)...%(else)...%(end). If there is an atom with
+ value or string literal after the %(if) then everything after
+ the %(then) is printed, else if the %(else) atom is used, then
+ everything after %(else) is printed. We ignore space when
+ evaluating the string before %(then), this is useful when we
+ use the %(HEAD) atom which prints either "*" or " " and we
+ want to apply the 'if' condition only on the 'HEAD' ref.
+
In addition to the above, for commit and tag objects, the header
field names (`tree`, `parent`, `object`, `type`, and `tag`) can
be used to specify the value in the header field.
@@ -181,6 +191,14 @@ As a special case for the date-type fields, you may specify a format for
the date by adding `:` followed by date format name (see the
values the `--date` option to linkgit:git-rev-list[1] takes).
+Some atoms like %(align) and %(if) always require a matching %(end).
+We call them "opening atoms" and sometimes denote them as %($open).
+
+When a scripting language specific quoting is in effect, everything
+between a top-level opening atom and its matching %(end) is evaluated
+according to the semantics of the opening atom and its result is
+quoted.
+
EXAMPLES
--------
@@ -268,6 +286,22 @@ eval=`git for-each-ref --shell --format="$fmt" \
eval "$eval"
------------
+
+An example to show the usage of %(if)...%(then)...%(else)...%(end).
+This prefixes the current branch with a star.
+
+------------
+git for-each-ref --format="%(if)%(HEAD)%(then)* %(else) %(end)%(refname:short)" refs/heads/
+------------
+
+
+An example to show the usage of %(if)...%(then)...%(end).
+This prints the authorname, if present.
+
+------------
+git for-each-ref --format="%(refname)%(if)%(authorname)%(then) %(color:red)Authored by: %(authorname)%(end)"
+------------
+
SEE ALSO
--------
linkgit:git-show-ref[1]
diff --git a/ref-filter.c b/ref-filter.c
index f5f7a70..2fed7fe 100644
--- a/ref-filter.c
+++ b/ref-filter.c
@@ -21,6 +21,12 @@ struct align {
unsigned int width;
};
+struct if_then_else {
+ unsigned int then_atom_seen : 1,
+ else_atom_seen : 1,
+ condition_satisfied : 1;
+};
+
/*
* An atom is a valid field atom listed below, possibly prefixed with
* a "*" to denote deref_tag().
@@ -203,6 +209,9 @@ static struct {
{ "color", FIELD_STR, color_atom_parser },
{ "align", FIELD_STR, align_atom_parser },
{ "end" },
+ { "if" },
+ { "then" },
+ { "else" },
};
#define REF_FORMATTING_STATE_INIT { 0, NULL }
@@ -210,7 +219,7 @@ static struct {
struct ref_formatting_stack {
struct ref_formatting_stack *prev;
struct strbuf output;
- void (*at_end)(struct ref_formatting_stack *stack);
+ void (*at_end)(struct ref_formatting_stack **stack);
void *at_end_data;
};
@@ -343,13 +352,14 @@ static void pop_stack_element(struct ref_formatting_stack **stack)
*stack = prev;
}
-static void end_align_handler(struct ref_formatting_stack *stack)
+static void end_align_handler(struct ref_formatting_stack **stack)
{
- struct align *align = (struct align *)stack->at_end_data;
+ struct ref_formatting_stack *cur = *stack;
+ struct align *align = (struct align *)cur->at_end_data;
struct strbuf s = STRBUF_INIT;
- strbuf_utf8_align(&s, align->position, align->width, stack->output.buf);
- strbuf_swap(&stack->output, &s);
+ strbuf_utf8_align(&s, align->position, align->width, cur->output.buf);
+ strbuf_swap(&cur->output, &s);
strbuf_release(&s);
}
@@ -363,6 +373,104 @@ static void align_atom_handler(struct atom_value *atomv, struct ref_formatting_s
new->at_end_data = &atomv->u.align;
}
+static void if_then_else_handler(struct ref_formatting_stack **stack)
+{
+ struct ref_formatting_stack *cur = *stack;
+ struct ref_formatting_stack *prev = cur->prev;
+ struct if_then_else *if_then_else = (struct if_then_else *)cur->at_end_data;
+
+ if (!if_then_else->then_atom_seen)
+ die(_("format: %%(if) atom used without a %%(then) atom"));
+
+ if (if_then_else->else_atom_seen) {
+ /*
+ * There is an %(else) atom: we need to drop one state from the
+ * stack, either the %(else) branch if the condition is satisfied, or
+ * the %(then) branch if it isn't.
+ */
+ if (if_then_else->condition_satisfied) {
+ strbuf_reset(&cur->output);
+ pop_stack_element(&cur);
+ } else {
+ strbuf_swap(&cur->output, &prev->output);
+ strbuf_reset(&cur->output);
+ pop_stack_element(&cur);
+ }
+ } else if (!if_then_else->condition_satisfied) {
+ /*
+ * No %(else) atom: just drop the %(then) branch if the
+ * condition is not satisfied.
+ */
+ strbuf_reset(&cur->output);
+ }
+
+ *stack = cur;
+ free(if_then_else);
+}
+
+static void if_atom_handler(struct atom_value *atomv, struct ref_formatting_state *state)
+{
+ struct ref_formatting_stack *new;
+ struct if_then_else *if_then_else = xcalloc(sizeof(struct if_then_else), 1);
+
+ push_stack_element(&state->stack);
+ new = state->stack;
+ new->at_end = if_then_else_handler;
+ new->at_end_data = if_then_else;
+}
+
+static int is_empty(const char *s)
+{
+ while (*s != '\0') {
+ if (!isspace(*s))
+ return 0;
+ s++;
+ }
+ return 1;
+}
+
+static void then_atom_handler(struct atom_value *atomv, struct ref_formatting_state *state)
+{
+ struct ref_formatting_stack *cur = state->stack;
+ struct if_then_else *if_then_else = NULL;
+
+ if (cur->at_end == if_then_else_handler)
+ if_then_else = (struct if_then_else *)cur->at_end_data;
+ if (!if_then_else)
+ die(_("format: %%(then) atom used without an %%(if) atom"));
+ if (if_then_else->then_atom_seen)
+ die(_("format: %%(then) atom used more than once"));
+ if (if_then_else->else_atom_seen)
+ die(_("format: %%(then) atom used after %%(else)"));
+ if_then_else->then_atom_seen = 1;
+ /*
+ * If there exists non-empty string between the 'if' and
+ * 'then' atom then the 'if' condition is satisfied.
+ */
+ if (cur->output.len && !is_empty(cur->output.buf))
+ if_then_else->condition_satisfied = 1;
+ strbuf_reset(&cur->output);
+}
+
+static void else_atom_handler(struct atom_value *atomv, struct ref_formatting_state *state)
+{
+ struct ref_formatting_stack *prev = state->stack;
+ struct if_then_else *if_then_else = NULL;
+
+ if (prev->at_end == if_then_else_handler)
+ if_then_else = (struct if_then_else *)prev->at_end_data;
+ if (!if_then_else)
+ die(_("format: %%(else) atom used without an %%(if) atom"));
+ if (!if_then_else->then_atom_seen)
+ die(_("format: %%(else) atom used without a %%(then) atom"));
+ if (if_then_else->else_atom_seen)
+ die(_("format: %%(else) atom used more than once"));
+ if_then_else->else_atom_seen = 1;
+ push_stack_element(&state->stack);
+ state->stack->at_end_data = prev->at_end_data;
+ state->stack->at_end = prev->at_end;
+}
+
static void end_atom_handler(struct atom_value *atomv, struct ref_formatting_state *state)
{
struct ref_formatting_stack *current = state->stack;
@@ -370,14 +478,17 @@ static void end_atom_handler(struct atom_value *atomv, struct ref_formatting_sta
if (!current->at_end)
die(_("format: %%(end) atom used without corresponding atom"));
- current->at_end(current);
+ current->at_end(&state->stack);
+
+ /* Stack may have been popped within at_end(), hence reset the current pointer */
+ current = state->stack;
/*
* Perform quote formatting when the stack element is that of
* a supporting atom. If nested then perform quote formatting
* only on the topmost supporting atom.
*/
- if (!state->stack->prev->prev) {
+ if (!current->prev->prev) {
quote_formatting(&s, current->output.buf, state->quote_style);
strbuf_swap(¤t->output, &s);
}
@@ -1029,6 +1140,15 @@ static void populate_value(struct ref_array_item *ref)
} else if (!strcmp(name, "end")) {
v->handler = end_atom_handler;
continue;
+ } else if (!strcmp(name, "if")) {
+ v->handler = if_atom_handler;
+ continue;
+ } else if (!strcmp(name, "then")) {
+ v->handler = then_atom_handler;
+ continue;
+ } else if (!strcmp(name, "else")) {
+ v->handler = else_atom_handler;
+ continue;
} else
continue;
diff --git a/t/t6302-for-each-ref-filter.sh b/t/t6302-for-each-ref-filter.sh
index d0ab09f..fed3013 100755
--- a/t/t6302-for-each-ref-filter.sh
+++ b/t/t6302-for-each-ref-filter.sh
@@ -327,4 +327,80 @@ test_expect_success 'reverse version sort' '
test_cmp expect actual
'
+test_expect_success 'improper usage of %(if), %(then), %(else) and %(end) atoms' '
+ test_must_fail git for-each-ref --format="%(if)" &&
+ test_must_fail git for-each-ref --format="%(then) %(end)" &&
+ test_must_fail git for-each-ref --format="%(else) %(end)" &&
+ test_must_fail git for-each-ref --format="%(if) %(else) %(end)" &&
+ test_must_fail git for-each-ref --format="%(if) %(then) %(then) %(end)" &&
+ test_must_fail git for-each-ref --format="%(then) %(else) %(end)" &&
+ test_must_fail git for-each-ref --format="%(if) %(else) %(end)" &&
+ test_must_fail git for-each-ref --format="%(if) %(then) %(else)" &&
+ test_must_fail git for-each-ref --format="%(if) %(else) %(then) %(end)" &&
+ test_must_fail git for-each-ref --format="%(if) %(then) %(else) %(else) %(end)" &&
+ test_must_fail git for-each-ref --format="%(if) %(end)"
+'
+
+test_expect_success 'check %(if)...%(then)...%(end) atoms' '
+ git for-each-ref --format="%(refname)%(if)%(authorname)%(then) Author: %(authorname)%(end)" >actual &&
+ cat >expect <<-\EOF &&
+ refs/heads/master Author: A U Thor
+ refs/heads/side Author: A U Thor
+ refs/odd/spot Author: A U Thor
+ refs/tags/annotated-tag
+ refs/tags/doubly-annotated-tag
+ refs/tags/doubly-signed-tag
+ refs/tags/foo1.10 Author: A U Thor
+ refs/tags/foo1.3 Author: A U Thor
+ refs/tags/foo1.6 Author: A U Thor
+ refs/tags/four Author: A U Thor
+ refs/tags/one Author: A U Thor
+ refs/tags/signed-tag
+ refs/tags/three Author: A U Thor
+ refs/tags/two Author: A U Thor
+ EOF
+ test_cmp expect actual
+'
+
+test_expect_success 'check %(if)...%(then)...%(else)...%(end) atoms' '
+ git for-each-ref --format="%(if)%(authorname)%(then)%(authorname)%(else)No author%(end): %(refname)" >actual &&
+ cat >expect <<-\EOF &&
+ A U Thor: refs/heads/master
+ A U Thor: refs/heads/side
+ A U Thor: refs/odd/spot
+ No author: refs/tags/annotated-tag
+ No author: refs/tags/doubly-annotated-tag
+ No author: refs/tags/doubly-signed-tag
+ A U Thor: refs/tags/foo1.10
+ A U Thor: refs/tags/foo1.3
+ A U Thor: refs/tags/foo1.6
+ A U Thor: refs/tags/four
+ A U Thor: refs/tags/one
+ No author: refs/tags/signed-tag
+ A U Thor: refs/tags/three
+ A U Thor: refs/tags/two
+ EOF
+ test_cmp expect actual
+'
+test_expect_success 'ignore spaces in %(if) atom usage' '
+ git for-each-ref --format="%(refname:short): %(if)%(HEAD)%(then)Head ref%(else)Not Head ref%(end)" >actual &&
+ cat >expect <<-\EOF &&
+ master: Head ref
+ side: Not Head ref
+ odd/spot: Not Head ref
+ annotated-tag: Not Head ref
+ doubly-annotated-tag: Not Head ref
+ doubly-signed-tag: Not Head ref
+ foo1.10: Not Head ref
+ foo1.3: Not Head ref
+ foo1.6: Not Head ref
+ four: Not Head ref
+ one: Not Head ref
+ signed-tag: Not Head ref
+ three: Not Head ref
+ two: Not Head ref
+ EOF
+ test_cmp expect actual
+'
+
test_done
--
2.10.2