Split Text.Pandoc.Version from Text.Pandoc.Shared.

This new module exports `pandocVersion` and `pandocVersionText`,
which are no longer exported from Text.Pandoc.Shared. [API change]

Also, we now set the `pandoc-version` variable centrally rather
than in the writers.  One effect is the man writer now emits
a comment with the pandoc version (this was intended before,
judging from the template, but it didn't happen because the
vairable wasn't set).

15 files changed, 49 insertions, 22 deletions

diff --git a/MANUAL.txt b/MANUAL.txt
index 04eaa282f..8feedc003 100644
--- a/MANUAL.txt
+++ b/MANUAL.txt
@@ -3158,6 +3158,9 @@ on the output format, and include the following:
 `curdir`
 :   working directory from which pandoc is run.
 
+`pandoc-version`
+:   pandoc version.
+
 `toc`
 :   non-null value if `--toc/--table-of-contents` was specified
 
diff --git a/pandoc-cli/lua/PandocCLI/Lua.hs b/pandoc-cli/lua/PandocCLI/Lua.hs
index 6507587c8..8c50e66b3 100644
--- a/pandoc-cli/lua/PandocCLI/Lua.hs
+++ b/pandoc-cli/lua/PandocCLI/Lua.hs
@@ -14,7 +14,7 @@ import HsLua.CLI (EnvBehavior (..), Settings (..), runStandalone)
 import Text.Pandoc.Class (runIOorExplode)
 import Text.Pandoc.Error (handleError)
 import Text.Pandoc.Lua (runLua, runLuaNoEnv, getEngine)
-import Text.Pandoc.Shared (pandocVersionText)
+import Text.Pandoc.Version (pandocVersionText)
 
 -- | Runs pandoc as a Lua interpreter that is (mostly) compatible with
 -- the default @lua@ program shipping with Lua.
diff --git a/pandoc-cli/src/pandoc.hs b/pandoc-cli/src/pandoc.hs
index 274b1c567..4415f7e69 100644
--- a/pandoc-cli/src/pandoc.hs
+++ b/pandoc-cli/src/pandoc.hs
@@ -24,7 +24,8 @@ import Data.Monoid (Any(..))
 import Control.Monad (when)
 import PandocCLI.Lua
 import PandocCLI.Server
-import Text.Pandoc.Shared (pandocVersion, defaultUserDataDir)
+import Text.Pandoc.Version (pandocVersion)
+import Text.Pandoc.Shared (defaultUserDataDir)
 import Text.Pandoc.Scripting (ScriptingEngine(..))
 import Data.Version (showVersion)
 import qualified Data.Text as T
diff --git a/pandoc-lua-engine/src/Text/Pandoc/Lua/Global.hs b/pandoc-lua-engine/src/Text/Pandoc/Lua/Global.hs
index 5ec7ced64..304ad8695 100644
--- a/pandoc-lua-engine/src/Text/Pandoc/Lua/Global.hs
+++ b/pandoc-lua-engine/src/Text/Pandoc/Lua/Global.hs
@@ -25,7 +25,7 @@ import Text.Pandoc.Lua.Marshal.ReaderOptions (pushReaderOptionsReadonly)
 import Text.Pandoc.Lua.Marshal.WriterOptions (pushWriterOptions)
 import Text.Pandoc.Lua.PandocLua ()
 import Text.Pandoc.Options (ReaderOptions, WriterOptions)
-import Text.Pandoc.Shared (pandocVersion)
+import Text.Pandoc.Version (pandocVersion)
 
 import qualified Data.Text as Text
 
diff --git a/pandoc.cabal b/pandoc.cabal
index dbe489f65..466cea2c2 100644
--- a/pandoc.cabal
+++ b/pandoc.cabal
@@ -636,7 +636,8 @@ library
                    Text.Pandoc.ImageSize,
                    Text.Pandoc.Class,
                    Text.Pandoc.Class.IO,
-                   Text.Pandoc.Citeproc
+                   Text.Pandoc.Citeproc,
+                   Text.Pandoc.Version
   other-modules:   Text.Pandoc.App.CommandLineOptions,
                    Text.Pandoc.App.FormatHeuristics,
                    Text.Pandoc.App.Input,
diff --git a/src/Text/Pandoc.hs b/src/Text/Pandoc.hs
index 2f2b396af..fb8a49334 100644
--- a/src/Text/Pandoc.hs
+++ b/src/Text/Pandoc.hs
@@ -73,7 +73,7 @@ import Text.Pandoc.Generic
 import Text.Pandoc.Logging
 import Text.Pandoc.Options
 import Text.Pandoc.Readers
-import Text.Pandoc.Shared (pandocVersion, pandocVersionText)
+import Text.Pandoc.Version (pandocVersion, pandocVersionText)
 import Text.Pandoc.Templates
 import Text.Pandoc.Translations (setTranslations, translateTerm)
 import Text.Pandoc.Writers
diff --git a/src/Text/Pandoc/App/OutputSettings.hs b/src/Text/Pandoc/App/OutputSettings.hs
index d38618198..56020cd1f 100644
--- a/src/Text/Pandoc/App/OutputSettings.hs
+++ b/src/Text/Pandoc/App/OutputSettings.hs
@@ -181,6 +181,8 @@ optToOutputSettings scriptingEngine opts = do
     >>=
     setVariableM "outputfile" (T.pack outputFile)
     >>=
+    setVariableM "pandoc-version" pandocVersionText
+    >>=
     setFilesVariableM "include-before" (optIncludeBeforeBody opts)
     >>=
     setFilesVariableM "include-after" (optIncludeAfterBody opts)
diff --git a/src/Text/Pandoc/Filter/JSON.hs b/src/Text/Pandoc/Filter/JSON.hs
index c3019c679..883e3c7c4 100644
--- a/src/Text/Pandoc/Filter/JSON.hs
+++ b/src/Text/Pandoc/Filter/JSON.hs
@@ -27,7 +27,8 @@ import Text.Pandoc.Definition (Pandoc)
 import Text.Pandoc.Error (PandocError (PandocFilterError))
 import Text.Pandoc.Filter.Environment (Environment (..))
 import Text.Pandoc.Process (pipeProcess)
-import Text.Pandoc.Shared (pandocVersionText, tshow)
+import Text.Pandoc.Version (pandocVersionText)
+import Text.Pandoc.Shared (tshow)
 import qualified Control.Exception as E
 import qualified Text.Pandoc.UTF8 as UTF8
 
diff --git a/src/Text/Pandoc/Shared.hs b/src/Text/Pandoc/Shared.hs
index 0a836847b..b2d14c52a 100644
--- a/src/Text/Pandoc/Shared.hs
+++ b/src/Text/Pandoc/Shared.hs
@@ -88,9 +88,6 @@ module Text.Pandoc.Shared (
                      safeStrRead,
                      -- * User data directory
                      defaultUserDataDir,
-                     -- * Version
-                     pandocVersion,
-                     pandocVersionText
                     ) where
 
 import Codec.Archive.Zip
@@ -110,8 +107,6 @@ import Data.Monoid (Any (..))
 import Data.Sequence (ViewL (..), ViewR (..), viewl, viewr)
 import qualified Data.Set as Set
 import qualified Data.Text as T
-import Data.Version (Version, showVersion)
-import Paths_pandoc (version)
 import System.Directory
 import System.FilePath (isPathSeparator, splitDirectories)
 import qualified System.FilePath.Posix as Posix
@@ -127,14 +122,6 @@ import Text.Pandoc.Generic (bottomUp)
 import Text.DocLayout (charWidth)
 import Text.Pandoc.Walk
 
--- | Version number of pandoc library.
-pandocVersion :: Version
-pandocVersion = version
-
--- | Text representation of the library's version number.
-pandocVersionText :: T.Text
-pandocVersionText = T.pack $ showVersion version
-
 --
 -- List processing
 --
diff --git a/src/Text/Pandoc/Version.hs b/src/Text/Pandoc/Version.hs
new file mode 100644
index 000000000..e5d1c2a74
--- /dev/null
+++ b/src/Text/Pandoc/Version.hs
@@ -0,0 +1,28 @@
+{-# LANGUAGE CPP                   #-}
+{- |
+   Module      : Text.Pandoc.Version
+   Copyright   : Copyright (C) 2022 John MacFarlane
+   License     : GNU GPL, version 2 or above
+
+   Maintainer  : John MacFarlane <[email protected]>
+   Stability   : alpha
+   Portability : portable
+
+Version information.
+-}
+module Text.Pandoc.Version (
+                     pandocVersion,
+                     pandocVersionText
+                    ) where
+
+import Data.Version (Version, showVersion)
+import Paths_pandoc (version)
+import qualified Data.Text as T
+
+-- | Version number of pandoc library.
+pandocVersion :: Version
+pandocVersion = version
+
+-- | Text representation of the library's version number.
+pandocVersionText :: T.Text
+pandocVersionText = T.pack $ showVersion version
diff --git a/src/Text/Pandoc/Writers/Man.hs b/src/Text/Pandoc/Writers/Man.hs
index fd4d52d3c..f4d829059 100644
--- a/src/Text/Pandoc/Writers/Man.hs
+++ b/src/Text/Pandoc/Writers/Man.hs
@@ -74,7 +74,7 @@ pandocToMan opts (Pandoc meta blocks) = do
               $ setFieldsFromTitle
               $ defField "has-tables" hasTables
               $ defField "hyphenate" True
-              $ defField "pandoc-version" pandocVersionText metadata
+              $ metadata
   return $ render colwidth $
     case writerTemplate opts of
        Nothing  -> main
diff --git a/src/Text/Pandoc/Writers/Ms.hs b/src/Text/Pandoc/Writers/Ms.hs
index 5592b3d86..ceff1697f 100644
--- a/src/Text/Pandoc/Writers/Ms.hs
+++ b/src/Text/Pandoc/Writers/Ms.hs
@@ -76,7 +76,6 @@ pandocToMs opts (Pandoc meta blocks) = do
   let context = defField "body" main
               $ defField "has-inline-math" hasInlineMath
               $ defField "hyphenate" True
-              $ defField "pandoc-version" pandocVersionText
               $ defField "toc" (writerTableOfContents opts)
               $ defField "title-meta" titleMeta
               $ defField "author-meta" (T.intercalate "; " authorsMeta)
diff --git a/src/Text/Pandoc/Writers/ODT.hs b/src/Text/Pandoc/Writers/ODT.hs
index 77289faea..302debe7f 100644
--- a/src/Text/Pandoc/Writers/ODT.hs
+++ b/src/Text/Pandoc/Writers/ODT.hs
@@ -35,7 +35,8 @@ import Text.Pandoc.Logging
 import Text.Pandoc.MIME (extensionFromMimeType, getMimeType)
 import Text.Pandoc.Options (WrapOption (..), WriterOptions (..))
 import Text.DocLayout
-import Text.Pandoc.Shared (stringify, pandocVersionText, tshow)
+import Text.Pandoc.Shared (stringify, tshow)
+import Text.Pandoc.Version (pandocVersionText)
 import Text.Pandoc.Writers.Shared (lookupMetaString, lookupMetaBlocks,
                                    fixDisplayMath, getLang,
                                    ensureValidXmlIdentifiers)
diff --git a/test/writer.man b/test/writer.man
index 30d83465f..752852322 100644
--- a/test/writer.man
+++ b/test/writer.man
@@ -1,3 +1,5 @@
+.\" Automatically generated by Pandoc 3.0
+.\"
 .\" Define V font for inline verbatim, using C font in formats
 .\" that render this, and otherwise B font.
 .ie "\f[CB]x\f[]"x" \{\
diff --git a/test/writer.ms b/test/writer.ms
index 5b00e2f15..fd78272d6 100644
--- a/test/writer.ms
+++ b/test/writer.ms
@@ -1,3 +1,5 @@
+.\" Automatically generated by Pandoc 3.0
+.\"
 .\" **** Custom macro definitions *********************************
 .\" * Super/subscript
 .\" (https://lists.gnu.org/archive/html/groff/2012-07/msg00046.html)