Switch from pretty-simple to pretty-show for native output.

Update tests.

Reason:  it turns out that the native output generated by
pretty-simple isn't always readable by the native reader.
According to https://github.com/cdepillabout/pretty-simple/issues/99
it is not a design goal of the library that the rendered values
be readable using 'read'.  This makes it unsuitable for our
purposes.

pretty-show is a bit slower and it uses 4-space indents
(non-configurable), but it doesn't have this serious drawback.

1 files changed, 163 insertions, 158 deletions

diff --git a/test/command/refs.md b/test/command/refs.md
index 165177175..d89e745ff 100644
--- a/test/command/refs.md
+++ b/test/command/refs.md
@@ -3,17 +3,18 @@
 Figure \ref{fig:1}
 ^D
 [ Para
-  [ Str "Figure"
-  , Space
-  , Link
-    ( ""
-    , []
-    ,
-      [ ( "reference-type", "ref" ), ( "reference", "fig:1" ) ]
-    )
-    [ Str "[fig:1]" ]
-    ( "#fig:1", "" )
-  ]
+    [ Str "Figure"
+    , Space
+    , Link
+        ( ""
+        , []
+        , [ ( "reference-type" , "ref" )
+          , ( "reference" , "fig:1" )
+          ]
+        )
+        [ Str "[fig:1]" ]
+        ( "#fig:1" , "" )
+    ]
 ]
 ```
 
@@ -22,17 +23,18 @@ Figure \ref{fig:1}
 Figure \cref{fig:1}
 ^D
 [ Para
-  [ Str "Figure"
-  , Space
-  , Link
-    ( ""
-    , []
-    ,
-      [ ( "reference-type", "ref" ), ( "reference", "fig:1" ) ]
-    )
-    [ Str "[fig:1]" ]
-    ( "#fig:1", "" )
-  ]
+    [ Str "Figure"
+    , Space
+    , Link
+        ( ""
+        , []
+        , [ ( "reference-type" , "ref" )
+          , ( "reference" , "fig:1" )
+          ]
+        )
+        [ Str "[fig:1]" ]
+        ( "#fig:1" , "" )
+    ]
 ]
 ```
 
@@ -41,17 +43,18 @@ Figure \cref{fig:1}
 Figure \vref{fig:1}
 ^D
 [ Para
-  [ Str "Figure"
-  , Space
-  , Link
-    ( ""
-    , []
-    ,
-      [ ( "reference-type", "ref+page" ), ( "reference", "fig:1" ) ]
-    )
-    [ Str "[fig:1]" ]
-    ( "#fig:1", "" )
-  ]
+    [ Str "Figure"
+    , Space
+    , Link
+        ( ""
+        , []
+        , [ ( "reference-type" , "ref+page" )
+          , ( "reference" , "fig:1" )
+          ]
+        )
+        [ Str "[fig:1]" ]
+        ( "#fig:1" , "" )
+    ]
 ]
 ```
 
@@ -65,36 +68,40 @@ Accuracy~\eqref{eq:Accuracy} is the proportion, measuring true results among all
 \end{equation}
 ^D
 [ Para
-  [ Str "Accuracy\160"
-  , Link
-    ( ""
-    , []
-    ,
-      [ ( "reference-type", "eqref" ), ( "reference", "eq:Accuracy" ) ]
-    )
-    [ Str "[eq:Accuracy]" ]
-    ( "#eq:Accuracy", "" )
-  , Space
-  , Str "is"
-  , Space
-  , Str "the"
-  , Space
-  , Str "proportion,"
-  , Space
-  , Str "measuring"
-  , Space
-  , Str "true"
-  , Space
-  , Str "results"
-  , Space
-  , Str "among"
-  , Space
-  , Str "all"
-  , Space
-  , Str "results."
-  ]
+    [ Str "Accuracy\160"
+    , Link
+        ( ""
+        , []
+        , [ ( "reference-type" , "eqref" )
+          , ( "reference" , "eq:Accuracy" )
+          ]
+        )
+        [ Str "[eq:Accuracy]" ]
+        ( "#eq:Accuracy" , "" )
+    , Space
+    , Str "is"
+    , Space
+    , Str "the"
+    , Space
+    , Str "proportion,"
+    , Space
+    , Str "measuring"
+    , Space
+    , Str "true"
+    , Space
+    , Str "results"
+    , Space
+    , Str "among"
+    , Space
+    , Str "all"
+    , Space
+    , Str "results."
+    ]
 , Para
-  [ Math DisplayMath "\\label{eq:Accuracy}\n  Accuracy = \\frac{t_p + t_n}{t_p + f_p + f_n + t_n}" ]
+    [ Math
+        DisplayMath
+        "\\label{eq:Accuracy}\n  Accuracy = \\frac{t_p + t_n}{t_p + f_p + f_n + t_n}"
+    ]
 ]
 ```
 
@@ -168,93 +175,90 @@ Figure \ref{fig:Logo2} illustrated the SVG logo
 
 Figure \ref{fig:Logo3} illustrated the SVG logo
 ^D
-[ Header 1
-  ( "one", [], [] )
-  [ Str "One" ]
+[ Header 1 ( "one" , [] , [] ) [ Str "One" ]
 , Para
-  [ Image
-    ( "fig:Logo", [], [] )
-    [ Str "Logo" ]
-    ( "command/SVG_logo.svg", "fig:" )
-  ]
+    [ Image
+        ( "fig:Logo" , [] , [] )
+        [ Str "Logo" ]
+        ( "command/SVG_logo.svg" , "fig:" )
+    ]
 , Para
-  [ Image
-    ( "fig:Logo2", [], [] )
-    [ Str "Logo2" ]
-    ( "command/SVG_logo2.svg", "fig:" )
-  ]
-, Header 1
-  ( "two", [], [] )
-  [ Str "Two" ]
-, Header 2
-  ( "subone", [], [] )
-  [ Str "Subone" ]
+    [ Image
+        ( "fig:Logo2" , [] , [] )
+        [ Str "Logo2" ]
+        ( "command/SVG_logo2.svg" , "fig:" )
+    ]
+, Header 1 ( "two" , [] , [] ) [ Str "Two" ]
+, Header 2 ( "subone" , [] , [] ) [ Str "Subone" ]
 , Para
-  [ Image
-    ( "fig:Logo3", [], [] )
-    [ Str "Logo3" ]
-    ( "command/SVG_logo3.svg", "fig:" )
-  ]
+    [ Image
+        ( "fig:Logo3" , [] , [] )
+        [ Str "Logo3" ]
+        ( "command/SVG_logo3.svg" , "fig:" )
+    ]
 , Para
-  [ Str "Figure"
-  , Space
-  , Link
-    ( ""
-    , []
-    ,
-      [ ( "reference-type", "ref" ), ( "reference", "fig:Logo" ) ]
-    )
-    [ Str "1.1" ]
-    ( "#fig:Logo", "" )
-  , Space
-  , Str "illustrated"
-  , Space
-  , Str "the"
-  , Space
-  , Str "SVG"
-  , Space
-  , Str "logo"
-  ]
+    [ Str "Figure"
+    , Space
+    , Link
+        ( ""
+        , []
+        , [ ( "reference-type" , "ref" )
+          , ( "reference" , "fig:Logo" )
+          ]
+        )
+        [ Str "1.1" ]
+        ( "#fig:Logo" , "" )
+    , Space
+    , Str "illustrated"
+    , Space
+    , Str "the"
+    , Space
+    , Str "SVG"
+    , Space
+    , Str "logo"
+    ]
 , Para
-  [ Str "Figure"
-  , Space
-  , Link
-    ( ""
-    , []
-    ,
-      [ ( "reference-type", "ref" ), ( "reference", "fig:Logo2" ) ]
-    )
-    [ Str "1.2" ]
-    ( "#fig:Logo2", "" )
-  , Space
-  , Str "illustrated"
-  , Space
-  , Str "the"
-  , Space
-  , Str "SVG"
-  , Space
-  , Str "logo"
-  ]
+    [ Str "Figure"
+    , Space
+    , Link
+        ( ""
+        , []
+        , [ ( "reference-type" , "ref" )
+          , ( "reference" , "fig:Logo2" )
+          ]
+        )
+        [ Str "1.2" ]
+        ( "#fig:Logo2" , "" )
+    , Space
+    , Str "illustrated"
+    , Space
+    , Str "the"
+    , Space
+    , Str "SVG"
+    , Space
+    , Str "logo"
+    ]
 , Para
-  [ Str "Figure"
-  , Space
-  , Link
-    ( ""
-    , []
-    ,
-      [ ( "reference-type", "ref" ), ( "reference", "fig:Logo3" ) ]
-    )
-    [ Str "2.1" ]
-    ( "#fig:Logo3", "" )
-  , Space
-  , Str "illustrated"
-  , Space
-  , Str "the"
-  , Space
-  , Str "SVG"
-  , Space
-  , Str "logo"
-  ]
+    [ Str "Figure"
+    , Space
+    , Link
+        ( ""
+        , []
+        , [ ( "reference-type" , "ref" )
+          , ( "reference" , "fig:Logo3" )
+          ]
+        )
+        [ Str "2.1" ]
+        ( "#fig:Logo3" , "" )
+    , Space
+    , Str "illustrated"
+    , Space
+    , Str "the"
+    , Space
+    , Str "SVG"
+    , Space
+    , Str "logo"
+    ]
 ]
 ```
 
@@ -264,20 +268,21 @@ Figure \ref{fig:Logo3} illustrated the SVG logo
 \label{section} Section \ref{section}
 ^D
 [ Para
-  [ Span
-    ( "section", [], [ ( "label", "section" ) ] )
-    [ Str "[section]" ]
-  , Space
-  , Str "Section"
-  , Space
-  , Link
-    ( ""
-    , []
-    ,
-      [ ( "reference-type", "ref" ), ( "reference", "section" ) ]
-    )
-    [ Str "[section]" ]
-    ( "#section", "" )
-  ]
+    [ Span
+        ( "section" , [] , [ ( "label" , "section" ) ] )
+        [ Str "[section]" ]
+    , Space
+    , Str "Section"
+    , Space
+    , Link
+        ( ""
+        , []
+        , [ ( "reference-type" , "ref" )
+          , ( "reference" , "section" )
+          ]
+        )
+        [ Str "[section]" ]
+        ( "#section" , "" )
+    ]
 ]
 ```