Add `xlsx` (Microsoft Excel) as an input format.

Each worksheet turns into a section containing a table.

The common file `nativeDiff` has been extract from
the Docx and Pptx text files and put in Tests.Helpers.

7 files changed, 446 insertions, 30 deletions

diff --git a/test/Tests/Helpers.hs b/test/Tests/Helpers.hs
index 3e930b14a..081611ed9 100644
--- a/test/Tests/Helpers.hs
+++ b/test/Tests/Helpers.hs
@@ -16,6 +16,7 @@ module Tests.Helpers ( test
                      , TestResult(..)
                      , setupEnvironment
                      , showDiff
+                     , nativeDiff
                      , testGolden
                      , (=?>)
                      , purely
@@ -132,6 +133,19 @@ vividize (Both s _) = "  " ++ s
 vividize (First s)  = "- " ++ s
 vividize (Second s) = "+ " ++ s
 
+nativeDiff :: FilePath -> Pandoc -> Pandoc -> IO (Maybe String)
+nativeDiff normPath expectedNative actualNative
+  | expectedNative == actualNative = return Nothing
+  | otherwise = Just <$> do
+      expected <- T.unpack <$> runIOorExplode (writeNative def expectedNative)
+      actual <- T.unpack <$> runIOorExplode (writeNative def actualNative)
+      let dash = replicate 72 '-'
+      let diff = getDiff (lines actual) (lines expected)
+      return $ '\n' : dash ++
+               "\n--- " ++ normPath ++
+               "\n+++ " ++ "test" ++ "\n" ++
+               showDiff (1,1) diff ++ dash
+
 purely :: (b -> PandocPure a) -> b -> a
 purely f = either (error . show) id . runPure . f
 
diff --git a/test/Tests/Readers/Docx.hs b/test/Tests/Readers/Docx.hs
index 0bd70d0e2..76af649b4 100644
--- a/test/Tests/Readers/Docx.hs
+++ b/test/Tests/Readers/Docx.hs
@@ -34,20 +34,6 @@ defopts = def{ readerExtensions = getDefaultExtensions "docx" }
 testCompare :: String -> FilePath -> FilePath -> TestTree
 testCompare = testCompareWithOpts defopts
 
-
-nativeDiff :: FilePath -> Pandoc -> Pandoc -> IO (Maybe String)
-nativeDiff normPath expectedNative actualNative
-  | expectedNative == actualNative = return Nothing
-  | otherwise = Just <$> do
-      expected <- T.unpack <$> runIOorExplode (writeNative def expectedNative)
-      actual <- T.unpack <$> runIOorExplode (writeNative def actualNative)
-      let dash = replicate 72 '-'
-      let diff = getDiff (lines actual) (lines expected)
-      return $ '\n' : dash ++
-               "\n--- " ++ normPath ++
-               "\n+++ " ++ "test" ++ "\n" ++
-               showDiff (1,1) diff ++ dash
-
 testCompareWithOpts :: ReaderOptions -> String -> FilePath -> FilePath -> TestTree
 testCompareWithOpts opts testName docxFP nativeFP =
   goldenTest
diff --git a/test/Tests/Readers/Pptx.hs b/test/Tests/Readers/Pptx.hs
index 613d5b50f..3358e4111 100644
--- a/test/Tests/Readers/Pptx.hs
+++ b/test/Tests/Readers/Pptx.hs
@@ -12,10 +12,8 @@ Tests for the PPTX reader.
 -}
 module Tests.Readers.Pptx (tests) where
 
-import Data.Algorithm.Diff (getDiff)
 import qualified Data.ByteString as BS
 import qualified Data.ByteString.Lazy as B
-import qualified Data.Text as T
 import Test.Tasty
 import Test.Tasty.Golden.Advanced
 import Tests.Helpers
@@ -28,19 +26,6 @@ defopts = def{ readerExtensions = getDefaultExtensions "pptx" }
 testCompare :: String -> FilePath -> FilePath -> TestTree
 testCompare = testCompareWithOpts defopts
 
-nativeDiff :: FilePath -> Pandoc -> Pandoc -> IO (Maybe String)
-nativeDiff normPath expectedNative actualNative
-  | expectedNative == actualNative = return Nothing
-  | otherwise = Just <$> do
-      expected <- T.unpack <$> runIOorExplode (writeNative def expectedNative)
-      actual <- T.unpack <$> runIOorExplode (writeNative def actualNative)
-      let dash = replicate 72 '-'
-      let diff = getDiff (lines actual) (lines expected)
-      return $ '\n' : dash ++
-               "\n--- " ++ normPath ++
-               "\n+++ " ++ "test" ++ "\n" ++
-               showDiff (1,1) diff ++ dash
-
 testCompareWithOpts :: ReaderOptions -> String -> FilePath -> FilePath -> TestTree
 testCompareWithOpts opts testName pptxFP nativeFP =
   goldenTest
diff --git a/test/Tests/Readers/Xlsx.hs b/test/Tests/Readers/Xlsx.hs
new file mode 100644
index 000000000..189cd0c16
--- /dev/null
+++ b/test/Tests/Readers/Xlsx.hs
@@ -0,0 +1,48 @@
+{-# LANGUAGE OverloadedStrings #-}
+{- |
+   Module      : Tests.Readers.Xlsx
+   Copyright   : © 2025 Anton Antic
+   License     : GNU GPL, version 2 or above
+
+   Maintainer  : Anton Antic <[email protected]>
+   Stability   : alpha
+   Portability : portable
+
+Tests for the XLSX reader.
+-}
+module Tests.Readers.Xlsx (tests) where
+
+import qualified Data.ByteString as BS
+import qualified Data.ByteString.Lazy as B
+import Test.Tasty
+import Test.Tasty.Golden.Advanced
+import Tests.Helpers
+import Text.Pandoc
+import Text.Pandoc.UTF8 as UTF8
+
+defopts :: ReaderOptions
+defopts = def{ readerExtensions = getDefaultExtensions "xlsx" }
+
+testCompare :: String -> FilePath -> FilePath -> TestTree
+testCompare = testCompareWithOpts defopts
+
+testCompareWithOpts :: ReaderOptions -> String -> FilePath -> FilePath -> TestTree
+testCompareWithOpts opts testName xlsxFP nativeFP =
+  goldenTest
+  testName
+  (do nf <- UTF8.toText <$> BS.readFile nativeFP
+      runIOorExplode (readNative def nf))
+  (do df <- B.readFile xlsxFP
+      runIOorExplode (readXlsx opts df))
+  (nativeDiff nativeFP)
+  (\a -> runIOorExplode (writeNative def{ writerTemplate = Just mempty} a)
+            >>= BS.writeFile nativeFP . UTF8.fromText)
+
+tests :: [TestTree]
+tests = [ testGroup "basic"
+          [ testCompare
+            "sheet extraction"
+            "xlsx-reader/basic.xlsx"
+            "xlsx-reader/basic.native"
+          ]
+        ]
diff --git a/test/test-pandoc.hs b/test/test-pandoc.hs
index 0d04b361f..9ae97d9c0 100644
--- a/test/test-pandoc.hs
+++ b/test/test-pandoc.hs
@@ -13,6 +13,7 @@ import qualified Tests.Old
 import qualified Tests.Readers.Creole
 import qualified Tests.Readers.Docx
 import qualified Tests.Readers.Pptx
+import qualified Tests.Readers.Xlsx
 import qualified Tests.Readers.DokuWiki
 import qualified Tests.Readers.EPUB
 import qualified Tests.Readers.FB2
@@ -97,6 +98,7 @@ tests pandocPath = testGroup "pandoc tests"
           , testGroup "RTF" Tests.Readers.RTF.tests
           , testGroup "Docx" Tests.Readers.Docx.tests
           , testGroup "Pptx" Tests.Readers.Pptx.tests
+          , testGroup "Xlsx" Tests.Readers.Xlsx.tests
           , testGroup "ODT" Tests.Readers.ODT.tests
           , testGroup "Txt2Tags" Tests.Readers.Txt2Tags.tests
           , testGroup "EPUB" Tests.Readers.EPUB.tests
@@ -126,4 +128,4 @@ main = do
     _ -> inDirectory "test" $ do
            fp <- getExecutablePath
            -- putStrLn $ "Using pandoc executable at " ++ fp
-           defaultMain $ tests fp
\ No newline at end of file
+           defaultMain $ tests fp
diff --git a/test/xlsx-reader/basic.native b/test/xlsx-reader/basic.native
new file mode 100644
index 000000000..f69f78a41
--- /dev/null
+++ b/test/xlsx-reader/basic.native
@@ -0,0 +1,381 @@
+Pandoc
+  Meta { unMeta = fromList [] }
+  [ Header 2 ( "sheet-1" , [] , [] ) [ Str "Main" ]
+  , Table
+      ( "" , [] , [] )
+      (Caption Nothing [])
+      [ ( AlignDefault , ColWidthDefault )
+      , ( AlignDefault , ColWidthDefault )
+      , ( AlignDefault , ColWidthDefault )
+      ]
+      (TableHead
+         ( "" , [] , [] )
+         [ Row
+             ( "" , [] , [] )
+             [ Cell
+                 ( "" , [] , [] )
+                 AlignDefault
+                 (RowSpan 1)
+                 (ColSpan 1)
+                 [ Plain [ Strong [ Str "Person" ] ] ]
+             , Cell
+                 ( "" , [] , [] )
+                 AlignDefault
+                 (RowSpan 1)
+                 (ColSpan 1)
+                 [ Plain [ Strong [ Str "Age" ] ] ]
+             , Cell
+                 ( "" , [] , [] )
+                 AlignDefault
+                 (RowSpan 1)
+                 (ColSpan 1)
+                 [ Plain [ Strong [ Str "Location" ] ] ]
+             ]
+         ])
+      [ TableBody
+          ( "" , [] , [] )
+          (RowHeadColumns 0)
+          []
+          [ Row
+              ( "" , [] , [] )
+              [ Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [ Str "Anton" , Space , Str "Antich" ] ]
+              , Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [ Str "23.0" ] ]
+              , Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [ Str "Switzerland" ] ]
+              ]
+          , Row
+              ( "" , [] , [] )
+              [ Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [ Str "James" , Space , Str "Bond" ] ]
+              , Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [ Str "35.0" ] ]
+              , Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [ Str "Moscow" ] ]
+              ]
+          , Row
+              ( "" , [] , [] )
+              [ Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [] ]
+              , Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [] ]
+              , Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [] ]
+              ]
+          , Row
+              ( "" , [] , [] )
+              [ Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [] ]
+              , Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [] ]
+              , Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [] ]
+              ]
+          , Row
+              ( "" , [] , [] )
+              [ Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain
+                      [ Str "Just"
+                      , Space
+                      , Str "a"
+                      , Space
+                      , Str "random"
+                      , Space
+                      , Str "cell"
+                      ]
+                  ]
+              , Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [] ]
+              , Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [] ]
+              ]
+          ]
+      ]
+      (TableFoot ( "" , [] , [] ) [])
+  , Header 2 ( "sheet-2" , [] , [] ) [ Str "Secondary" ]
+  , Table
+      ( "" , [] , [] )
+      (Caption Nothing [])
+      [ ( AlignDefault , ColWidthDefault )
+      , ( AlignDefault , ColWidthDefault )
+      , ( AlignDefault , ColWidthDefault )
+      , ( AlignDefault , ColWidthDefault )
+      , ( AlignDefault , ColWidthDefault )
+      ]
+      (TableHead
+         ( "" , [] , [] )
+         [ Row
+             ( "" , [] , [] )
+             [ Cell
+                 ( "" , [] , [] )
+                 AlignDefault
+                 (RowSpan 1)
+                 (ColSpan 1)
+                 [ Plain
+                     [ Str "Sum"
+                     , Space
+                     , Str "of"
+                     , Space
+                     , Str "Age"
+                     ]
+                 ]
+             , Cell
+                 ( "" , [] , [] )
+                 AlignDefault
+                 (RowSpan 1)
+                 (ColSpan 1)
+                 [ Plain [ Str "Column" , Space , Str "Labels" ] ]
+             , Cell
+                 ( "" , [] , [] )
+                 AlignDefault
+                 (RowSpan 1)
+                 (ColSpan 1)
+                 [ Plain [] ]
+             , Cell
+                 ( "" , [] , [] )
+                 AlignDefault
+                 (RowSpan 1)
+                 (ColSpan 1)
+                 [ Plain [] ]
+             , Cell
+                 ( "" , [] , [] )
+                 AlignDefault
+                 (RowSpan 1)
+                 (ColSpan 1)
+                 [ Plain [] ]
+             ]
+         ])
+      [ TableBody
+          ( "" , [] , [] )
+          (RowHeadColumns 0)
+          []
+          [ Row
+              ( "" , [] , [] )
+              [ Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [ Str "Row" , Space , Str "Labels" ] ]
+              , Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [ Str "Moscow" ] ]
+              , Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [ Str "Switzerland" ] ]
+              , Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [ Str "(blank)" ] ]
+              , Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [ Str "Grand" , Space , Str "Total" ] ]
+              ]
+          , Row
+              ( "" , [] , [] )
+              [ Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [ Str "Anton" , Space , Str "Antich" ] ]
+              , Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [] ]
+              , Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [ Str "23.0" ] ]
+              , Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [] ]
+              , Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [ Str "23.0" ] ]
+              ]
+          , Row
+              ( "" , [] , [] )
+              [ Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [ Str "James" , Space , Str "Bond" ] ]
+              , Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [ Str "35.0" ] ]
+              , Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [] ]
+              , Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [] ]
+              , Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [ Str "35.0" ] ]
+              ]
+          , Row
+              ( "" , [] , [] )
+              [ Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [ Str "(blank)" ] ]
+              , Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [] ]
+              , Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [] ]
+              , Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [] ]
+              , Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [] ]
+              ]
+          , Row
+              ( "" , [] , [] )
+              [ Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [ Str "Grand" , Space , Str "Total" ] ]
+              , Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [ Str "35.0" ] ]
+              , Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [ Str "23.0" ] ]
+              , Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [] ]
+              , Cell
+                  ( "" , [] , [] )
+                  AlignDefault
+                  (RowSpan 1)
+                  (ColSpan 1)
+                  [ Plain [ Str "58.0" ] ]
+              ]
+          ]
+      ]
+      (TableFoot ( "" , [] , [] ) [])
+  ]
diff --git a/test/xlsx-reader/basic.xlsx b/test/xlsx-reader/basic.xlsx
new file mode 100644
index 000000000..55d62d56e
--- /dev/null
+++ b/test/xlsx-reader/basic.xlsx