[gtk+] css: Add initial support for calc()

[Benjamin Otte <otte src gnome org>]

commit cd6dc954f2bd173903d805fe3c4810ae25e82490
Author: Benjamin Otte <otte redhat com>
Date:   Fri Feb 12 06:56:14 2016 +0100

    css: Add initial support for calc()
    
    So far, calc() only supports literals, ie it's completely useless.

 gtk/Makefile.am                          |    2 +
 gtk/gtkcsscalcvalue.c                    |  152 ++++++++++++++++++++++++++++++
 gtk/gtkcsscalcvalueprivate.h             |   30 ++++++
 gtk/gtkcssnumbervalue.c                  |    7 +-
 testsuite/css/parser/Makefile.am         |    2 +
 testsuite/css/parser/calc-simple.css     |   31 ++++++
 testsuite/css/parser/calc-simple.ref.css |   41 ++++++++
 7 files changed, 264 insertions(+), 1 deletions(-)
---
diff --git a/gtk/Makefile.am b/gtk/Makefile.am
index 5c2875c..7bf26a6 100644
--- a/gtk/Makefile.am
+++ b/gtk/Makefile.am
@@ -387,6 +387,7 @@ gtk_private_h_sources =             \
        gtkcssarrayvalueprivate.h       \
        gtkcssbgsizevalueprivate.h      \
        gtkcssbordervalueprivate.h      \
+       gtkcsscalcvalueprivate.h        \
        gtkcsscolorvalueprivate.h       \
        gtkcsscornervalueprivate.h      \
        gtkcsscustomgadgetprivate.h     \
@@ -652,6 +653,7 @@ gtk_base_c_sources =                \
        gtkcssarrayvalue.c      \
        gtkcssbgsizevalue.c     \
        gtkcssbordervalue.c     \
+       gtkcsscalcvalue.c       \
        gtkcsscolorvalue.c      \
        gtkcsscornervalue.c     \
        gtkcsscustomgadget.c    \
diff --git a/gtk/gtkcsscalcvalue.c b/gtk/gtkcsscalcvalue.c
new file mode 100644
index 0000000..51839c0
--- /dev/null
+++ b/gtk/gtkcsscalcvalue.c
@@ -0,0 +1,152 @@
+/* GTK - The GIMP Toolkit
+ * Copyright © 2016 Benjamin Otte <otte gnome org>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "config.h"
+
+#include "gtkcsscalcvalueprivate.h"
+
+#include "gtkcssenumvalueprivate.h"
+#include "gtkcssinitialvalueprivate.h"
+#include "gtkstylepropertyprivate.h"
+
+#include "fallback-c89.c"
+
+struct _GtkCssValue {
+  GTK_CSS_VALUE_BASE
+  GtkCssValue *term;
+};
+
+static void
+gtk_css_value_calc_free (GtkCssValue *value)
+{
+  _gtk_css_value_unref (value->term);
+  g_slice_free (GtkCssValue, value);
+}
+
+static GtkCssValue *gtk_css_calc_value_new (GtkCssValue *term);
+
+static GtkCssValue *
+gtk_css_value_calc_compute (GtkCssValue             *calc,
+                            guint                    property_id,
+                            GtkStyleProviderPrivate *provider,
+                            GtkCssStyle             *style,
+                            GtkCssStyle             *parent_style)
+{
+  GtkCssValue *computed_term;
+
+  computed_term = _gtk_css_value_compute (calc->term, property_id, provider, style, parent_style);
+  if (computed_term == calc->term)
+    return _gtk_css_value_ref (calc);
+
+  return gtk_css_calc_value_new (computed_term);
+}
+
+
+static gboolean
+gtk_css_value_calc_equal (const GtkCssValue *calc1,
+                          const GtkCssValue *calc2)
+{
+  return _gtk_css_value_equal (calc1->term, calc2->term);
+}
+
+static GtkCssValue *
+gtk_css_value_calc_transition (GtkCssValue *start,
+                               GtkCssValue *end,
+                               guint        property_id,
+                               double       progress)
+{
+  return NULL;
+}
+
+static void
+gtk_css_value_calc_print (const GtkCssValue *calc,
+                          GString           *string)
+{
+  g_string_append (string, "calc(");
+  _gtk_css_value_print (calc->term, string);
+  g_string_append (string, ")");
+}
+
+double
+gtk_css_value_calc_get (const GtkCssValue *value,
+                        double             one_hundred_percent)
+{
+  return _gtk_css_number_value_get (value->term, one_hundred_percent);
+}
+
+GtkCssDimension
+gtk_css_value_calc_get_dimension (const GtkCssValue *value)
+{
+  return gtk_css_number_value_get_dimension (value->term);
+}
+
+gboolean
+gtk_css_value_calc_has_percent (const GtkCssValue *value)
+{
+  return gtk_css_number_value_has_percent (value->term);
+}
+
+static const GtkCssNumberValueClass GTK_CSS_VALUE_CALC = {
+  {
+    gtk_css_value_calc_free,
+    gtk_css_value_calc_compute,
+    gtk_css_value_calc_equal,
+    gtk_css_value_calc_transition,
+    gtk_css_value_calc_print
+  },
+  gtk_css_value_calc_get,
+  gtk_css_value_calc_get_dimension,
+  gtk_css_value_calc_has_percent,
+};
+
+static GtkCssValue *
+gtk_css_calc_value_new (GtkCssValue *term)
+{
+  GtkCssValue *result;
+
+  result = _gtk_css_value_new (GtkCssValue, &GTK_CSS_VALUE_CALC.value_class);
+  result->term = term;
+
+  return result;
+}
+
+GtkCssValue *
+gtk_css_calc_value_parse (GtkCssParser           *parser,
+                          GtkCssNumberParseFlags  flags)
+{
+  GtkCssValue *term;
+
+  if (!_gtk_css_parser_try (parser, "calc(", TRUE))
+    {
+      _gtk_css_parser_error (parser, "Expected 'calc('");
+      return NULL;
+    }
+
+  term = _gtk_css_number_value_parse (parser, flags);
+  if (term == NULL)
+    return NULL;
+
+  if (!_gtk_css_parser_try (parser, ")", TRUE))
+    {
+      _gtk_css_value_unref (term);
+      _gtk_css_parser_error (parser, "Expected ')' for calc() statement");
+      return NULL;
+    }
+
+  return gtk_css_calc_value_new (term);
+}
+
diff --git a/gtk/gtkcsscalcvalueprivate.h b/gtk/gtkcsscalcvalueprivate.h
new file mode 100644
index 0000000..247d4c8
--- /dev/null
+++ b/gtk/gtkcsscalcvalueprivate.h
@@ -0,0 +1,30 @@
+/*
+ * Copyright © 2016 Benjamin Otte <otte gnome org>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __GTK_CSS_CALC_VALUE_PRIVATE_H__
+#define __GTK_CSS_CALC_VALUE_PRIVATE_H__
+
+#include "gtkcssnumbervalueprivate.h"
+
+G_BEGIN_DECLS
+
+GtkCssValue *   gtk_css_calc_value_parse            (GtkCssParser           *parser,
+                                                     GtkCssNumberParseFlags  flags);
+
+G_END_DECLS
+
+#endif /* __GTK_CSS_CALC_VALUE_PRIVATE_H__ */
diff --git a/gtk/gtkcssnumbervalue.c b/gtk/gtkcssnumbervalue.c
index 05643d7..12508db 100644
--- a/gtk/gtkcssnumbervalue.c
+++ b/gtk/gtkcssnumbervalue.c
@@ -19,6 +19,7 @@
 
 #include "gtkcssnumbervalueprivate.h"
 
+#include "gtkcsscalcvalueprivate.h"
 #include "gtkcssdimensionvalueprivate.h"
 
 struct _GtkCssValue {
@@ -51,13 +52,17 @@ _gtk_css_number_value_new (double     value,
 gboolean
 gtk_css_number_value_can_parse (GtkCssParser *parser)
 {
-  return _gtk_css_parser_has_number (parser);
+  return _gtk_css_parser_has_number (parser)
+      || _gtk_css_parser_has_prefix (parser, "calc");
 }
 
 GtkCssValue *
 _gtk_css_number_value_parse (GtkCssParser           *parser,
                              GtkCssNumberParseFlags  flags)
 {
+  if (_gtk_css_parser_has_prefix (parser, "calc"))
+    return gtk_css_calc_value_parse (parser, flags);
+
   return gtk_css_dimension_value_parse (parser, flags);
 }
 
diff --git a/testsuite/css/parser/Makefile.am b/testsuite/css/parser/Makefile.am
index a90b869..28fa71f 100644
--- a/testsuite/css/parser/Makefile.am
+++ b/testsuite/css/parser/Makefile.am
@@ -226,6 +226,8 @@ test_data = \
         border-width.ref.css \
         box-shadow.css \
         box-shadow.ref.css \
+       calc-simple.css \
+       calc-simple.ref.css \
        close-at-end-of-file.css \
        close-at-end-of-file.errors \
        close-at-end-of-file.ref.css \
diff --git a/testsuite/css/parser/calc-simple.css b/testsuite/css/parser/calc-simple.css
new file mode 100644
index 0000000..ca5327d
--- /dev/null
+++ b/testsuite/css/parser/calc-simple.css
@@ -0,0 +1,31 @@
+a {
+  margin: calc(1px) calc(0px) calc(-3px);
+}
+
+b {
+  background-position: calc(50%) calc(0%);
+}
+
+c {
+  background-image: linear-gradient(calc(45deg), red calc(0%), green calc(100%));
+}
+
+d {
+  border-radius: calc(1px) calc(2px) / calc(1em) calc(2em) calc(3em);
+}
+
+e {
+  border-top-left-radius: calc(50%);
+}
+
+f {
+  border-image-source: radial-gradient(circle calc(20px) at calc(50%) calc(25%), red calc(0%), blue 
calc(100%));
+}
+
+g {
+  border-left: calc(1px);
+}
+
+h {
+  border-right: red calc(2px);
+}
diff --git a/testsuite/css/parser/calc-simple.ref.css b/testsuite/css/parser/calc-simple.ref.css
new file mode 100644
index 0000000..2c4c66f
--- /dev/null
+++ b/testsuite/css/parser/calc-simple.ref.css
@@ -0,0 +1,41 @@
+a {
+  margin-bottom: -3px;
+  margin-left: 0;
+  margin-right: 0;
+  margin-top: 1px;
+}
+
+b {
+  background-position: top;
+}
+
+c {
+  background-image: linear-gradient(45deg, rgb(255,0,0) 0, rgb(0,128,0) 100%);
+}
+
+d {
+  border-bottom-left-radius: 2px 2em;
+  border-bottom-right-radius: 1px 3em;
+  border-top-left-radius: 1px 1em;
+  border-top-right-radius: 2px 2em;
+}
+
+e {
+  border-top-left-radius: 50%;
+}
+
+f {
+  border-image-source: radial-gradient(circle 20px at center 25%, rgb(255,0,0) 0, rgb(0,0,255) 100%);
+}
+
+g {
+  border-left-color: initial;
+  border-left-style: initial;
+  border-left-width: 1px;
+}
+
+h {
+  border-right-color: rgb(255,0,0);
+  border-right-style: initial;
+  border-right-width: 2px;
+}