Docx reader: Support new table features.

* Column spans
* Row spans
  - The spec says that if the `val` attribute is ommitted, its value
    should be assumed to be `continue`, and that its values are
    restricted to {`restart`, `continue`}. If the value has any other
    value, I think it seems reasonable to default it to `continue`. It
    might cause problems if the spec is extended in the future by adding
    a third possible value, in which case this would probably give
    incorrect behaviour, and wouldn't error.
* Allow multiple header rows
* Include table description in simple caption
  - The table description element is like alt text for a table (along
    with the table caption element). It seems like we should include
    this somewhere, but I’m not 100% sure how – I’m pairing it with the
    simple caption for the moment. (Should it maybe go in the block
    caption instead?)
* Detect table captions
  - Check for caption paragraph style /and/ either the simple or
    complex table field. This means the caption detection fails for
    captions which don’t contain a field, as in an example doc I added
    as a test. However, I think it’s better to be too conservative: a
    missed table caption will still show up as a paragraph next to the
    table, whereas if I incorrectly classify something else as a table
    caption it could cause havoc by pairing it up with a table it’s
    not at all related to, or dropping it entirely.
* Update tests and add new ones

Partially fixes: #6316

1 files changed, 54 insertions, 0 deletions

diff --git a/test/docx/table_captions_with_field.native b/test/docx/table_captions_with_field.native
new file mode 100644
index 000000000..deb8afc6b
--- /dev/null
+++ b/test/docx/table_captions_with_field.native
@@ -0,0 +1,54 @@
+[Para [Str "See",Space,Str "Table",Space,Str "1."]
+,Para []
+,Table ("",[],[]) (Caption Nothing
+ [Para [Str "Table",Space,Str "1"]])
+ [(AlignDefault,ColWidth 0.7605739372523825)
+ ,(AlignDefault,ColWidth 0.11971303137380876)
+ ,(AlignDefault,ColWidth 0.11971303137380876)]
+ (TableHead ("",[],[])
+[Row ("",[],[])
+ [Cell ("",[],[]) AlignDefault (RowSpan 1) (ColSpan 1)
+  []
+ ,Cell ("",[],[]) AlignDefault (RowSpan 1) (ColSpan 1)
+  [Plain [Str "Count"]]
+ ,Cell ("",[],[]) AlignDefault (RowSpan 1) (ColSpan 1)
+  [Plain [Str "%"]]]])
+ [(TableBody ("",[],[]) (RowHeadColumns 0)
+  []
+  [Row ("",[],[])
+ [Cell ("",[],[]) AlignDefault (RowSpan 1) (ColSpan 1)
+  [Plain [Str "First",Space,Str "option"]]
+ ,Cell ("",[],[]) AlignDefault (RowSpan 1) (ColSpan 1)
+  [Plain [Str "242"]]
+ ,Cell ("",[],[]) AlignDefault (RowSpan 1) (ColSpan 1)
+  [Plain [Str "45"]]]
+,Row ("",[],[])
+ [Cell ("",[],[]) AlignDefault (RowSpan 1) (ColSpan 1)
+  [Plain [Str "Second",Space,Str "option"]]
+ ,Cell ("",[],[]) AlignDefault (RowSpan 1) (ColSpan 1)
+  [Plain [Str "99"]]
+ ,Cell ("",[],[]) AlignDefault (RowSpan 1) (ColSpan 1)
+  [Plain [Str "18"]]]])]
+ (TableFoot ("",[],[])
+ [])
+,Header 2 ("section", [], []) []
+,Table ("",[],[]) (Caption Nothing
+ [Para [Str "Table",Space,Str "2"]])
+ [(AlignDefault,ColWidth 0.3332963620230701)
+ ,(AlignDefault,ColWidth 0.3332963620230701)
+ ,(AlignDefault,ColWidth 0.3334072759538598)]
+ (TableHead ("",[],[])
+ [Row ("",[],[])
+  [Cell ("",[],[]) AlignDefault (RowSpan 1) (ColSpan 1)
+   [Plain [Str "One"]]
+  ,Cell ("",[],[]) AlignDefault (RowSpan 1) (ColSpan 1)
+   [Plain [Str "Two"]]
+  ,Cell ("",[],[]) AlignDefault (RowSpan 1) (ColSpan 1)
+   [Plain [Str "Three"]]]])
+ [(TableBody ("",[],[]) (RowHeadColumns 0)
+  []
+  [])]
+ (TableFoot ("",[],[])
+ [])
+,Para []
+,Para [Str "See",Space,Str "Table",Space,Str "2."]]