Improve sizer flags validation in the XRC schema.

Validate flags for 1D horizontal and vertical sizers and grid sizers
separately to allow checking for invalid flag combinations.

Also try to make the regex patterns used in the schema itself and the error
messages generated when matching them fails slightly more readable.

misc/schema/xrc_schema.rnc

@@ -230,12 +230,15 @@ builtinWindowClasses =
     )
 
 builtinSizerClasses =
-    ( wxBoxSizer
+    ( wxBoxSizer_horz
-    | wxStaticBoxSizer
+    | wxBoxSizer_vert
+    | wxStaticBoxSizer_horz
+    | wxStaticBoxSizer_vert
     | wxGridSizer
     | wxFlexGridSizer
     | wxGridBagSizer
-    | wxWrapSizer
+    | wxWrapSizer_horz
+    | wxWrapSizer_vert
     | wxStdDialogButtonSizer
     )
 
@@ -1565,9 +1568,123 @@ wxWizardPage_any =
     }
 
 
+# There is no simple way to validate the combination of flags using "|" symbol,
+# so we have to resort to regular expressions here. They are long and unwieldy
+# which is especially bad for the error messages, so we try to make them more
+# clear by inserting a dummy match element providing the description of the
+# expected value.
+#
+# And to make writing and reading patterns simpler in this schema itself, we
+# always put the part containing the always allowed flags on a (very long) line
+# of its own (the one starting with "wxALL").
+
+t_sizer_flags_grow = xsd:string {
+        pattern = "(wxGROW|wxEXPAND" ~
+                  "|wxALL|wxLEFT|wxRIGHT|wxTOP|wxBOTTOM|wxNORTH|wxSOUTH|wxEAST|wxWEST|wxSHAPED|wxSTRETCH_NOT|wxRESERVE_SPACE_EVEN_IF_HIDDEN)" ~
+                  "( *\| *" ~
+                  "(wxGROW|wxEXPAND" ~
+                  "|wxALL|wxLEFT|wxRIGHT|wxTOP|wxBOTTOM|wxNORTH|wxSOUTH|wxEAST|wxWEST|wxSHAPED|wxSTRETCH_NOT|wxRESERVE_SPACE_EVEN_IF_HIDDEN)" ~
+                  ")*"
+    }
+
+t_sizer_flags_alignv = xsd:string {
+        pattern = "(wxALIGN_CENTER|wxALIGN_CENTRE" ~
+                  "|wxALIGN_CENTER_VERTICAL|wxALIGN_CENTRE_VERTICAL" ~
+                  "|wxALIGN_TOP|wxALIGN_BOTTOM" ~
+                  "|wxALL|wxLEFT|wxRIGHT|wxTOP|wxBOTTOM|wxNORTH|wxSOUTH|wxEAST|wxWEST|wxSHAPED|wxSTRETCH_NOT|wxRESERVE_SPACE_EVEN_IF_HIDDEN)" ~
+                  "( *\| *" ~
+                  "(wxALIGN_CENTER|wxALIGN_CENTRE" ~
+                  "|wxALIGN_CENTER_VERTICAL|wxALIGN_CENTRE_VERTICAL" ~
+                  "|wxALIGN_TOP|wxALIGN_BOTTOM" ~
+                  "|wxALL|wxLEFT|wxRIGHT|wxTOP|wxBOTTOM|wxNORTH|wxSOUTH|wxEAST|wxWEST|wxSHAPED|wxSTRETCH_NOT|wxRESERVE_SPACE_EVEN_IF_HIDDEN)" ~
+                  ")*"
+    }
+
+t_sizer_flags_alignh = xsd:string {
+        pattern = "(wxALIGN_CENTER|wxALIGN_CENTRE" ~
+                  "|wxALIGN_CENTER_HORIZONTAL|wxALIGN_CENTRE_HORIZONTAL" ~
+                  "|wxALIGN_LEFT|wxALIGN_RIGHT" ~
+                  "|wxALL|wxLEFT|wxRIGHT|wxTOP|wxBOTTOM|wxNORTH|wxSOUTH|wxEAST|wxWEST|wxSHAPED|wxSTRETCH_NOT|wxRESERVE_SPACE_EVEN_IF_HIDDEN)" ~
+                  "( *\| *" ~
+                  "(wxALIGN_CENTER|wxALIGN_CENTRE" ~
+                  "|wxALIGN_CENTER_HORIZONTAL|wxALIGN_CENTRE_HORIZONTAL" ~
+                  "|wxALIGN_LEFT|wxALIGN_RIGHT" ~
+                  "|wxALL|wxLEFT|wxRIGHT|wxTOP|wxBOTTOM|wxNORTH|wxSOUTH|wxEAST|wxWEST|wxSHAPED|wxSTRETCH_NOT|wxRESERVE_SPACE_EVEN_IF_HIDDEN)" ~
+                  ")*"
+    }
+
+t_horz_sizer_flags = ("*** Sizer flags excluding vertical alignment ones ***"
+        | t_sizer_flags_grow
+        | t_sizer_flags_alignv
+        )
+t_vert_sizer_flags = ("*** Sizer flags excluding horizontal alignment ones ***"
+        | t_sizer_flags_grow
+        | t_sizer_flags_alignh
+        )
+
+t_sizer_flags_grow_alignv = xsd:string {
+        pattern = "(wxALIGN_CENTER|wxALIGN_CENTRE" ~
+                  "|wxALIGN_CENTER_VERTICAL|wxALIGN_CENTRE_VERTICAL" ~
+                  "|wxALIGN_TOP|wxALIGN_BOTTOM" ~
+                  "|wxGROW|wxEXPAND" ~
+                  "|wxALL|wxLEFT|wxRIGHT|wxTOP|wxBOTTOM|wxNORTH|wxSOUTH|wxEAST|wxWEST|wxSHAPED|wxSTRETCH_NOT|wxRESERVE_SPACE_EVEN_IF_HIDDEN)" ~
+                  "( *\| *" ~
+                  "(wxALIGN_CENTER|wxALIGN_CENTRE" ~
+                  "|wxALIGN_CENTER_VERTICAL|wxALIGN_CENTRE_VERTICAL" ~
+                  "|wxALIGN_TOP|wxALIGN_BOTTOM" ~
+                  "|wxGROW|wxEXPAND" ~
+                  "|wxALL|wxLEFT|wxRIGHT|wxTOP|wxBOTTOM|wxNORTH|wxSOUTH|wxEAST|wxWEST|wxSHAPED|wxSTRETCH_NOT|wxRESERVE_SPACE_EVEN_IF_HIDDEN)" ~
+                  ")*"
+    }
+
+t_sizer_flags_grow_alignh = xsd:string {
+        pattern = "(wxALIGN_CENTER|wxALIGN_CENTRE" ~
+                  "|wxALIGN_CENTER_HORIZONTAL|wxALIGN_CENTRE_HORIZONTAL" ~
+                  "|wxALIGN_LEFT|wxALIGN_RIGHT" ~
+                  "|wxGROW|wxEXPAND" ~
+                  "|wxALL|wxLEFT|wxRIGHT|wxTOP|wxBOTTOM|wxNORTH|wxSOUTH|wxEAST|wxWEST|wxSHAPED|wxSTRETCH_NOT|wxRESERVE_SPACE_EVEN_IF_HIDDEN)" ~
+                  "( *\| *" ~
+                  "(wxALIGN_CENTER|wxALIGN_CENTRE" ~
+                  "|wxALIGN_CENTER_HORIZONTAL|wxALIGN_CENTRE_HORIZONTAL" ~
+                  "|wxALIGN_LEFT|wxALIGN_RIGHT" ~
+                  "|wxGROW|wxEXPAND" ~
+                  "|wxALL|wxLEFT|wxRIGHT|wxTOP|wxBOTTOM|wxNORTH|wxSOUTH|wxEAST|wxWEST|wxSHAPED|wxSTRETCH_NOT|wxRESERVE_SPACE_EVEN_IF_HIDDEN)" ~
+                  ")*"
+    }
+
+t_sizer_flags_align = xsd:string {
+        pattern = "(wxALIGN_CENTER|wxALIGN_CENTRE" ~
+                  "|wxALIGN_CENTER_HORIZONTAL|wxALIGN_CENTRE_HORIZONTAL" ~
+                  "|wxALIGN_CENTER_VERTICAL|wxALIGN_CENTRE_VERTICAL" ~
+                  "|wxALIGN_LEFT|wxALIGN_RIGHT" ~
+                  "|wxALIGN_TOP|wxALIGN_BOTTOM" ~
+                  "|wxALL|wxLEFT|wxRIGHT|wxTOP|wxBOTTOM|wxNORTH|wxSOUTH|wxEAST|wxWEST|wxSHAPED|wxSTRETCH_NOT|wxRESERVE_SPACE_EVEN_IF_HIDDEN)" ~
+                  "( *\| *" ~
+                  "(wxALIGN_CENTER|wxALIGN_CENTRE" ~
+                  "|wxALIGN_CENTER_HORIZONTAL|wxALIGN_CENTRE_HORIZONTAL" ~
+                  "|wxALIGN_CENTER_VERTICAL|wxALIGN_CENTRE_VERTICAL" ~
+                  "|wxALIGN_LEFT|wxALIGN_RIGHT" ~
+                  "|wxALIGN_TOP|wxALIGN_BOTTOM" ~
+                  "|wxALL|wxLEFT|wxRIGHT|wxTOP|wxBOTTOM|wxNORTH|wxSOUTH|wxEAST|wxWEST|wxSHAPED|wxSTRETCH_NOT|wxRESERVE_SPACE_EVEN_IF_HIDDEN)" ~
+                  ")*"
+    }
+
+t_grid_sizer_flags = ("*** Sizer flags with either wxGROW/wxEXPAND or alignment in each direction ***"
+        | t_sizer_flags_grow
+        | t_sizer_flags_grow_alignv
+        | t_sizer_flags_grow_alignh
+        | t_sizer_flags_align
+        )
 
 
-wxSizer_item =
+# The items of different sizers are very similar but not quite identical:
+#  - For 1D sizers we need to define 2 versions to ensure that alignment flags
+#    in the major sizer direction are not accepted.
+#  - Only 1D sizers have "option" attribute.
+#  - For 2D sizers we accept alignment flags in both directions but not when
+#    combined with wxGROW and/or wxEXPAND.
+#  - Only wxGridBagSizer items have cell{pos,span} attributes.
+wxBoxSizer_horz_item =
     element object {
         (
             (
@@ -1585,7 +1702,67 @@ wxSizer_item =
         [xrc:p="o"] element border   {_, t_dimension }* &
         [xrc:p="o"] element minsize  {_, t_size }* &
         [xrc:p="o"] element ratio    {_, t_size }* &
-        # TODO: cell{pos,span} are wxGridBagSizer-only and required in it, this is too lax
+        [xrc:p="o"] element flag     {_, t_horz_sizer_flags}*
+    }
+
+wxBoxSizer_vert_item =
+    element object {
+        (
+            (
+                attribute class { "spacer" } &
+                [xrc:p="o"] element size {_, t_size }*
+            )
+            |
+            (
+                attribute class { "sizeritem" } &
+                (windowNode | sizerNode)
+            )
+        ) &
+        stdObjectNodeAttributes &
+        [xrc:p="o"] element option   {_, t_integer }* &
+        [xrc:p="o"] element border   {_, t_dimension }* &
+        [xrc:p="o"] element minsize  {_, t_size }* &
+        [xrc:p="o"] element ratio    {_, t_size }* &
+        [xrc:p="o"] element flag     {_, t_vert_sizer_flags }*
+    }
+
+wxGridSizer_item =
+    element object {
+        (
+            (
+                attribute class { "spacer" } &
+                [xrc:p="o"] element size {_, t_size }*
+            )
+            |
+            (
+                attribute class { "sizeritem" } &
+                (windowNode | sizerNode)
+            )
+        ) &
+        stdObjectNodeAttributes &
+        [xrc:p="o"] element border   {_, t_dimension }* &
+        [xrc:p="o"] element minsize  {_, t_size }* &
+        [xrc:p="o"] element ratio    {_, t_size }* &
+        [xrc:p="o"] element flag     {_, t_grid_sizer_flags }*
+    }
+
+wxSizerGB_item =
+    element object {
+        (
+            (
+                attribute class { "spacer" } &
+                [xrc:p="o"] element size {_, t_size }*
+            )
+            |
+            (
+                attribute class { "sizeritem" } &
+                (windowNode | sizerNode)
+            )
+        ) &
+        stdObjectNodeAttributes &
+        [xrc:p="o"] element border   {_, t_dimension }* &
+        [xrc:p="o"] element minsize  {_, t_size }* &
+        [xrc:p="o"] element ratio    {_, t_size }* &
         [xrc:p="o"] element cellpos  {_, t_position }* &
         [xrc:p="o"] element cellspan {_, t_size }* &
         [xrc:p="o"] element flag     {_,
@@ -1595,23 +1772,45 @@ wxSizer_item =
         }*
     }
 
-wxBoxSizer =
+# Notice that horizontal orientation is the default (only for backwards
+# compatibility reasons, it would make more sense to require always specifying
+# it probably).
+wxBoxSizer_horz =
     element object {
         attribute class { "wxBoxSizer" } &
         stdObjectNodeAttributes &
         [xrc:p="o"] element minsize {_, t_size }* &
-        [xrc:p="o"] element orient  {_, ("wxHORIZONTAL" | "wxVERTICAL") }* &
+        [xrc:p="o"] element orient {_, "wxHORIZONTAL" }* &
-        (wxSizer_item | objectRef)*
+        (wxBoxSizer_horz_item | objectRef)*
     }
 
-wxStaticBoxSizer =
+wxBoxSizer_vert =
+    element object {
+        attribute class { "wxBoxSizer" } &
+        stdObjectNodeAttributes &
+        [xrc:p="o"] element minsize {_, t_size }* &
+        element orient {_, "wxVERTICAL" } &
+        (wxBoxSizer_vert_item | objectRef)*
+    }
+
+wxStaticBoxSizer_horz =
     element object {
         attribute class { "wxStaticBoxSizer" } &
         stdObjectNodeAttributes &
         [xrc:p="o"] element minsize {_, t_size }* &
         [xrc:p="important"] element label {_, t_text }* &
-        [xrc:p="o"] element orient  {_, ("wxHORIZONTAL" | "wxVERTICAL") }* &
+        [xrc:p="o"] element orient  {_, "wxHORIZONTAL" }* &
-        (wxSizer_item | objectRef)*
+        (wxBoxSizer_horz_item | objectRef)*
+    }
+
+wxStaticBoxSizer_vert =
+    element object {
+        attribute class { "wxStaticBoxSizer" } &
+        stdObjectNodeAttributes &
+        [xrc:p="o"] element minsize {_, t_size }* &
+        [xrc:p="important"] element label {_, t_text }* &
+        element orient {_, "wxVERTICAL" } &
+        (wxBoxSizer_vert_item | objectRef)*
     }
 
 wxGridSizer =
@@ -1623,7 +1822,7 @@ wxGridSizer =
         [xrc:p="o"] element cols    {_, t_unsigned }* &
         [xrc:p="o"] element vgap    {_, t_dimension }* &
         [xrc:p="o"] element hgap    {_, t_dimension }* &
-        (wxSizer_item | objectRef)*
+        (wxGridSizer_item | objectRef)*
     }
 
 wxFlexGridSizer =
@@ -1641,7 +1840,7 @@ wxFlexGridSizer =
                                                      "wxFLEX_GROWMODE_ALL") }* &
         [xrc:p="o"] element growablerows        {_, t_list_of_numbers }* &
         [xrc:p="o"] element growablecols        {_, t_list_of_numbers }* &
-        (wxSizer_item | objectRef)*
+        (wxGridSizer_item | objectRef)*
     }
 
 wxGridBagSizer =
@@ -1657,17 +1856,27 @@ wxGridBagSizer =
                                                      "wxFLEX_GROWMODE_ALL") }* &
         [xrc:p="o"] element growablerows        {_, t_list_of_numbers }* &
         [xrc:p="o"] element growablecols        {_, t_list_of_numbers }* &
-        (wxSizer_item | objectRef)*
+        (wxSizerGB_item | objectRef)*
     }
 
-wxWrapSizer =
+wxWrapSizer_horz =
     element object {
         attribute class { "wxWrapSizer" } &
         stdObjectNodeAttributes &
         [xrc:p="o"] element minsize {_, t_size }* &
-        [xrc:p="important"] element orient {_, ("wxHORIZONTAL" | "wxVERTICAL") }* &
+        [xrc:p="important"] element orient {_, "wxHORIZONTAL" }* &
         [xrc:p="o"] element flag    {_, t_style }* &
-        (wxSizer_item | objectRef)*
+        (wxBoxSizer_horz_item | objectRef)*
+    }
+
+wxWrapSizer_vert =
+    element object {
+        attribute class { "wxWrapSizer" } &
+        stdObjectNodeAttributes &
+        [xrc:p="o"] element minsize {_, t_size }* &
+        element orient {_, "wxVERTICAL" } &
+        [xrc:p="o"] element flag    {_, t_style }* &
+        (wxBoxSizer_vert_item | objectRef)*
     }
 
 wxStdDialogButtonSizer =