Implement TabArray class (#50)

docs/binding-progress.rst

@@ -311,19 +311,19 @@ ______________________
 * PangoAttrList
 * PANGO_TYPE_ATTR_LIST
 * PangoAttrIterator
-* pango_tab_array_new ()
+* ✔ pango_tab_array_new ()
 * pango_tab_array_new_with_positions ()
-* pango_tab_array_copy ()
-* pango_tab_array_free ()
-* pango_tab_array_get_size ()
-* pango_tab_array_resize ()
-* pango_tab_array_set_tab ()
-* pango_tab_array_get_tab ()
-* pango_tab_array_get_tabs ()
+* ✔ pango_tab_array_copy ()
+* ✔ pango_tab_array_free ()
+* ✔ pango_tab_array_get_size ()
+* ✔ pango_tab_array_resize ()
+* ✔ pango_tab_array_set_tab ()
+* ✔ pango_tab_array_get_tab ()
+* ✔ pango_tab_array_get_tabs ()
 * pango_tab_array_get_positions_in_pixels ()
-* PangoTabArray
+* ✔ PangoTabArray
 * PANGO_TYPE_TAB_ARRAY
-* PangoTabAlign
+* ✔ PangoTabAlign
 * PANGO_TYPE_TAB_ALIGN
 * ✔︎ pango_layout_new ()
 * pango_layout_copy ()

docs/modules.rst

@@ -120,7 +120,15 @@ Tab Stops
 
 Structures for storing tab stops.
 
-API not implemented yet.
+TabArray
+________
+
+.. autoclass:: TabArray
+
+TabAlign
+________
+
+.. autoclass:: TabAlign
 
 Text Attribute Markup
 =====================
@@ -230,4 +238,4 @@ ________________
 Pango Object
 ____________
 
-.. autoclass:: PangoObject
+.. autoclass:: PangoObject

pangocffi/__init__.py

@@ -63,6 +63,7 @@ def _dlopen(dl_name: str, generated_ffi, names: List[str]):
 from .glyph_item_iter import GlyphItemIter  # noqa
 from .attribute import Attribute  # noqa
 from .attr_list import AttrList  # noqa
+from .tabarray import TabArray # noqa
 from .layout_run import LayoutRun  # noqa
 from .layout_iter import LayoutIter  # noqa
 from .layout import Layout  # noqa

pangocffi/c_definitions_glib.txt

@@ -8,7 +8,7 @@ typedef int gint32;
 typedef gint gboolean;
 typedef char gchar;
 typedef unsigned char guchar;
-typedef ... gunichar;
+typedef guint32 gunichar;
 typedef void* gpointer;
 typedef ... gconstpointer;
 typedef ... GObject;
@@ -22,4 +22,4 @@ typedef ... GMarkupParseContext;
 typedef ... GTypeModule;
 
 void g_object_unref (gpointer object);
-void g_free (gpointer mem);
+void g_free (gpointer mem);

pangocffi/c_definitions_pango.txt

@@ -1065,7 +1065,10 @@ void pango_script_iter_free (PangoScriptIter *iter);
 PangoLanguage *pango_script_get_sample_language (PangoScript script) ;
 typedef enum
 {
- PANGO_TAB_LEFT
+ PANGO_TAB_LEFT,
+ PANGO_TAB_RIGHT,
+ PANGO_TAB_CENTER,
+ PANGO_TAB_DECIMAL
 } PangoTabAlign;
 PangoTabArray *pango_tab_array_new (gint initial_size,
  gboolean positions_in_pixels);
@@ -1092,6 +1095,9 @@ void pango_tab_array_get_tabs (PangoTabArray *tab_array,
  PangoTabAlign **alignments,
  gint **locations);
 gboolean pango_tab_array_get_positions_in_pixels (PangoTabArray *tab_array);
+void pango_tab_array_set_positions_in_pixels (PangoTabArray *tab_array, gboolean positions_in_pixels);
+void pango_tab_array_set_decimal_point (PangoTabArray *tab_array, int tab_index, gunichar decimal_point);
+gunichar pango_tab_array_get_decimal_point (PangoTabArray *tab_array, int tab_index);
 int pango_units_from_double (double d) ;
 double pango_units_to_double (int i) ;
 void pango_extents_to_pixels (PangoRectangle *inclusive,

pangocffi/enums.py

@@ -239,3 +239,34 @@ class Underline(Enum):
     mispelling; in some cases a contrasting color may
     automatically be used. This type of underlining is available
     since Pango 1.4."""
+
+
+class TabAlign(Enum):
+    """
+    :class:`TabAlign` specifies where the text appears relative to the
+    tab stop position.
+    """
+
+    LEFT = pango.PANGO_TAB_LEFT
+    """
+    The text appears to the right of the tab stop position.
+    """
+
+    RIGHT = pango.PANGO_TAB_RIGHT
+    """
+    The text appears to the left of the tab stop position until the
+    available space is filled. Since: 1.50
+    """
+
+    CENTER = pango.PANGO_TAB_CENTER
+    """
+    The text is centered at the tab stop position until the available
+    space is filled. Since: 1.50
+    """
+
+    DECIMAL = pango.PANGO_TAB_DECIMAL
+    """
+    Text before the first occurrence of the decimal point character
+    appears to the left of the tab stop position (until the available
+    space is filled), the rest to the right. Since: 1.50
+    """

pangocffi/layout.py

@@ -1,5 +1,5 @@
 from . import pango, gobject, ffi, PangoObject
-from . import Context, FontDescription, AttrList
+from . import Context, FontDescription, AttrList, TabArray
 from . import Alignment, Rectangle, EllipsizeMode, WrapMode
 from pangocffi import LayoutIter
 from typing import Tuple, Optional
@@ -165,6 +165,18 @@ def _del_attributes(self) -> None:
     :param attrs: a :class:`AttrList`
     """
 
+    def _get_tabs(self) -> TabArray:
+        tabs_pointer = pango.pango_layout_get_tabs(self._pointer)
+        return TabArray(tabs_pointer)
+
+    def _set_tabs(self, tabs: TabArray) -> None:
+        pango.pango_layout_set_tabs(self._pointer, tabs._pointer)
+
+    tabs: str = property(_get_tabs, _set_tabs)
+    """
+    The tab stops for this layout.
+    """
+
     def apply_markup(self, markup: str) -> None:
         """
         Sets the layout text and attribute list from marked-up text.

pangocffi/tabarray.py

@@ -0,0 +1,86 @@
+from . import pango, ffi, PangoObject, TabAlign
+from typing import List, Tuple, Optional
+
+
+class TabArray(PangoObject):
+
+    _INIT_METHOD = pango.pango_tab_array_new
+    _GC_METHOD = pango.pango_tab_array_free
+    _COPY_METHOD = pango.pango_tab_array_copy
+
+    def __init__(self):
+        return super().__init__(None, 0, False)
+
+    def __len__(self):
+        return pango.pango_tab_array_get_size(self._pointer)
+
+    def _get_tabs(self) -> List[Tuple[TabAlign, int]]:
+        size = len(self)
+        alignments = ffi.new("PangoTabAlign**")
+        locations = ffi.new("gint**")
+        pango.pango_tab_array_get_tabs(self._pointer, alignments, locations)
+        if alignments[0] == ffi.NULL or locations[0] == ffi.NULL:
+            return []
+        else:
+            return [(TabAlign(alignments[0][i]), locations[0][i])
+                    for i in range(size)]
+
+    def _set_tabs(self, tabs: List[Tuple[TabAlign, int]]) -> None:
+        pango.pango_tab_array_resize(self._pointer, len(tabs))
+        for i in range(len(tabs)):
+            pango.pango_tab_array_set_tab(self._pointer, i, tabs[i][0].value,
+                                          tabs[i][1])
+
+    tabs: str = property(_get_tabs, _set_tabs)
+    """
+    Alignment and location of the tabs.
+    """
+
+    def _get_decimal_point(self) -> List[Optional[str]]:
+        size = len(self)
+        ret = []
+        for i in range(size):
+            decimal_point = pango.pango_tab_array_get_decimal_point(
+                            self._pointer, i)
+            if decimal_point == 0:
+                ret.append(None)
+            else:
+                ret.append(chr(decimal_point))
+        return ret
+
+    def _set_decimal_point(self, decimal_point: List[Optional[str]]) -> None:
+        if len(decimal_point) != len(self):
+            raise IndexError()
+        for i in range(len(decimal_point)):
+            value = ord(decimal_point[i]) if decimal_point[i] is not None \
+                                          else 0
+            pango.pango_tab_array_set_decimal_point(self._pointer, i, value)
+
+    decimal_point: str = property(_get_decimal_point, _set_decimal_point)
+    """
+    Unicode character to use as decimal point.
+
+    This is only relevant for tabs with :attr:`TabAlign.DECIMAL`
+    alignment, which align content at the first occurrence of the decimal
+    point character.
+
+    The default value of :const:`None` means that Pango will use the
+    decimal point according to the current locale.
+
+    :raises: :class:`IndexError` when trying to assign more or less
+      elements than defined tab stops.
+    """
+
+    def _set_positions_in_pixels(self, positions_in_pixels: bool) -> None:
+        pango.pango_tab_array_set_positions_in_pixels(self._pointer,
+                                                      positions_in_pixels)
+
+    def _get_positions_in_pixels(self) -> bool:
+        return pango.pango_tab_array_get_positions_in_pixels(self._pointer) \
+               != 0
+
+    positions_in_pixels = property(_get_positions_in_pixels,
+                                   _set_positions_in_pixels)
+    """
+    True if tab positions are in pixels.
+    """

tests/functional/test_tabarray.py

@@ -0,0 +1,36 @@
+from pangocffi import (
+    TabArray, TabAlign
+)
+import unittest
+
+
+class TestTabArray(unittest.TestCase):
+    def test_identity(self):
+        tabarray = TabArray()
+        assert len(tabarray) == 0
+        tabs = [(TabAlign.LEFT, 1), (TabAlign.LEFT, 10)]
+        tabarray.tabs = tabs
+        assert len(tabarray) == len(tabs)
+        assert tabarray.tabs == tabs
+
+        decimal_point = [':', ',']
+        tabarray.decimal_point = decimal_point
+        assert tabarray.decimal_point == decimal_point
+
+        assert tabarray.positions_in_pixels is False
+        tabarray.positions_in_pixels = True
+        assert tabarray.positions_in_pixels is True
+
+    def test_zero_size(self):
+        tabarray = TabArray()
+        assert len(tabarray) == 0
+        assert tabarray.tabs == []
+
+    def test_decimal_point_none(self):
+        tabarray = TabArray()
+
+        tabs = [(TabAlign.LEFT, 1), (TabAlign.LEFT, 10)]
+        tabarray.tabs = tabs
+        decimal_point = [None, None]
+        tabarray.decimal_point = decimal_point
+        assert tabarray.decimal_point == decimal_point