Adding support for rich display of Markdown cells in HTML and LaTeX o…

…utput (#2390)

NEWS.md

@@ -65,3 +65,5 @@
 
 * Documentation is now available also in *Dark* mode
   ([#2315](https://github.com/JuliaData/DataFrames.jl/pull/2315))
+* add rich display support for Markdown cell entries in HTML and LaTeX
+  ([#2346](https://github.com/JuliaData/DataFrames.jl/pull/2346))

Project.toml

@@ -10,6 +10,7 @@ Future = "9fa8497b-333b-5362-9e8d-4d0656e87820"
 InvertedIndices = "41ab1584-1d38-5bbf-9106-f11c6c58b48f"
 IteratorInterfaceExtensions = "82899510-4779-5014-852e-03e436cf321d"
 LinearAlgebra = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"
+Markdown = "d6f4376e-aef5-505a-96c1-9c027394607a"
 Missings = "e1d29d7a-bbdc-5cf2-9ac0-f12de2c33e28"
 PooledArrays = "2dfb63ee-cc39-5dd5-95bd-886bf059d720"
 Printf = "de0858da-6303-5e67-8744-51eddeeeb8d7"

src/DataFrames.jl

@@ -6,6 +6,7 @@ using Reexport, SortingAlgorithms, Compat, Unicode, PooledArrays
 using Base.Sort, Base.Order, Base.Iterators
 using TableTraits, IteratorInterfaceExtensions
 import LinearAlgebra: norm
+using Markdown
 
 import DataAPI,
        DataAPI.All,

src/abstractdataframe/io.jl

@@ -142,6 +142,10 @@ function _show(io::IO, ::MIME"text/html", df::AbstractDataFrame;
                 cell_val = df[row, column_name]
                 if ismissing(cell_val)
                     write(io, "<td><em>missing</em></td>")
+                elseif cell_val isa Markdown.MD
+                    write(io, "<td>")
+                    show(io, "text/html", cell_val)
+                    write(io, "</td>")
                 elseif cell_val isa SHOW_TABULAR_TYPES
                     write(io, "<td><em>")
                     cell = sprint(ourshow, cell_val)
@@ -302,6 +306,8 @@ function _show(io::IO, ::MIME"text/latex", df::AbstractDataFrame;
                 cell = df[row,col]
                 if ismissing(cell)
                     print(io, "\\emph{missing}")
+                elseif cell isa Markdown.MD
+                    print(io, strip(repr(MIME("text/latex"), cell)))
                 elseif cell isa SHOW_TABULAR_TYPES
                     print(io, "\\emph{")
                     print(io, latex_escape(sprint(ourshow, cell, context=io)))
@@ -410,17 +416,23 @@ function printtable(io::IO,
     quotestr = string(quotemark)
     for i in 1:n
         for j in 1:p
-            if ismissing(df[i, j])
+            cell = df[i, j]
+            if ismissing(cell)
                 print(io, missingstring)
-            elseif isnothing(df[i, j])
+            elseif isnothing(cell)
                 print(io, nothingstring)
             else
-                if ! (etypes[j] <: Real)
+                if cell isa Markdown.MD
                     print(io, quotemark)
-                    escapedprint(io, df[i, j], quotestr)
+                    r = repr(cell)
+                    escapedprint(io, chomp(r), quotestr)
+                    print(io, quotemark)
+                elseif ! (etypes[j] <: Real)
+                    print(io, quotemark)
+                    escapedprint(io, cell, quotestr)
                     print(io, quotemark)
                 else
-                    print(io, df[i, j])
+                    print(io, cell)
                 end
             end
             if j < p

src/abstractdataframe/show.jl

@@ -54,6 +54,11 @@ ourshow(io::IO, x::Symbol) = ourshow(io, string(x))
 ourshow(io::IO, x::Nothing; styled::Bool=false) = ourshow(io, "", styled=styled)
 ourshow(io::IO, x::SHOW_TABULAR_TYPES; styled::Bool=false) =
     ourshow(io, summary(x), styled=styled)
+function ourshow(io::IO, x::Markdown.MD)
+    r = repr(x)
+    len = min(length(r, 1, something(findfirst(==('\n'), r), lastindex(r)+1)-1), 32)
+    return print(io, len < length(r) - 1 ? first(r, len)*'…' : first(r, len))
+end
 
 # AbstractChar: https://github.com/JuliaLang/julia/pull/34730 (1.5.0-DEV.261)
 # Irrational: https://github.com/JuliaLang/julia/pull/34741 (1.5.0-DEV.266)

test/io.jl

@@ -1,28 +1,30 @@
 module TestIO
 
-using Test, DataFrames, CategoricalArrays, Dates
+using Test, DataFrames, CategoricalArrays, Dates, Markdown
 
 # Test LaTeX export
 @testset "LaTeX export" begin
-    df = DataFrame(A = 1:4,
+    df = DataFrame(A = Int64.( 1:4 ),
                 B = ["\$10.0", "M&F", "A~B", "\\alpha"],
                 C = ["A", "B", "C", "S"],
                 D = [1.0, 2.0, missing, 3.0],
                 E = CategoricalArray(["a", missing, "c", "d"]),
-                F = Vector{String}(undef, 4)
+                F = Vector{String}(undef, 4),
+                G = [ md"[DataFrames.jl](http://juliadata.github.io/DataFrames.jl)", md"###A", md"``\frac{A}{B}``", md"*A*b**A**"]
                 )
     str = """
-        \\begin{tabular}{r|cccccc}
-        \t& A & B & C & D & E & F\\\\
+        \\begin{tabular}{r|ccccccc}
+        \t& A & B & C & D & E & F & G\\\\
         \t\\hline
-        \t& $(Int) & String & String & Float64? & Cat…? & String\\\\
+        \t& Int64 & String & String & Float64? & Cat…? & String & MD…\\\\
         \t\\hline
-        \t1 & 1 & \\\$10.0 & A & 1.0 & a & \\emph{\\#undef} \\\\
-        \t2 & 2 & M\\&F & B & 2.0 & \\emph{missing} & \\emph{\\#undef} \\\\
-        \t3 & 3 & A\\textasciitilde{}B & C & \\emph{missing} & c & \\emph{\\#undef} \\\\
-        \t4 & 4 & \\textbackslash{}\\textbackslash{}alpha & S & 3.0 & d & \\emph{\\#undef} \\\\
+        \t1 & 1 & \\\$10.0 & A & 1.0 & a & \\emph{\\#undef} & \\href{http://juliadata.github.io/DataFrames.jl}{DataFrames.jl} \\\\
+        \t2 & 2 & M\\&F & B & 2.0 & \\emph{missing} & \\emph{\\#undef} & \\#\\#\\#A \\\\
+        \t3 & 3 & A\\textasciitilde{}B & C & \\emph{missing} & c & \\emph{\\#undef} & \$\\frac{A}{B}\$ \\\\
+        \t4 & 4 & \\textbackslash{}\\textbackslash{}alpha & S & 3.0 & d & \\emph{\\#undef} & \\emph{A}b\\textbf{A} \\\\
         \\end{tabular}
         """
+
     @test repr(MIME("text/latex"), df) == str
     @test repr(MIME("text/latex"), eachcol(df)) == str
     @test repr(MIME("text/latex"), eachrow(df)) == str
@@ -130,6 +132,27 @@ end
 
     @test_throws ArgumentError DataFrames._show(stdout, MIME("text/html"),
                                                 DataFrame(ones(2,2)), rowid=10)
+
+    df = DataFrame(
+        A=Int64[1,4,9,16],
+        B = [
+            md"[DataFrames.jl](http://juliadata.github.io/DataFrames.jl)",
+            md"###A",
+            md"``\frac{A}{B}``",
+            md"*A*b**A**" ]
+    )
+
+    @test repr(MIME("text/html"), df) ==
+        "<table class=\"data-frame\"><thead><tr><th></th><th>A</th><th>B</th></tr><tr><th></th>" *
+        "<th>Int64</th><th>MD…</th></tr></thead><tbody><p>4 rows × 2 columns</p><tr><th>1</th>" *
+        "<td>1</td><td><div class=\"markdown\">" *
+        "<p><a href=\"http://juliadata.github.io/DataFrames.jl\">DataFrames.jl</a>" *
+        "</p>\n</div></td></tr><tr><th>2</th><td>4</td><td><div class=\"markdown\">" *
+        "<p>###A</p>\n</div></td></tr><tr><th>3</th><td>9</td><td><div class=\"markdown\">" *
+        "<p>&#36;\\frac&#123;A&#125;&#123;B&#125;&#36;</p>\n</div></td></tr><tr><th>4</th>" *
+        "<td>16</td><td><div class=\"markdown\"><p><em>A</em>b<strong>A</strong></p>"*
+        "\n</div></td></tr></tbody></table>"
+
 end
 
 # test limit attribute of IOContext is used
@@ -180,6 +203,101 @@ end
     end
 end
 
+@testset "Markdown as text/plain and as text/csv" begin
+    df = DataFrame(
+        A=Int64[1,4,9,16,25,36,49,64],
+        B = [
+            md"[DataFrames.jl](http://juliadata.github.io/DataFrames.jl)",
+            md"``\frac{x^2}{x^2+y^2}``",
+            md"# Header",
+            md"This is *very*, **very**, very, very, very, very, very, very, very long line" ,
+            md"",
+            Markdown.parse("∫αγ∞1∫αγ∞2∫αγ∞3∫αγ∞4∫αγ∞5∫αγ∞6∫αγ∞7∫αγ∞8∫αγ∞9∫αγ∞0∫αγ∞1∫αγ∞2∫αγ∞3"),
+            Markdown.parse("∫αγ∞1∫αγ∞\n"*
+                           "  * 2∫αγ∞3∫αγ∞4\n"*
+                           "  * ∫αγ∞5∫αγ\n"*
+                           "  * ∞6∫αγ∞7∫αγ∞8∫αγ∞9∫αγ∞0"),
+            Markdown.parse("∫αγ∞1∫αγ∞2∫αγ∞3∫αγ∞4∫αγ∞5∫αγ∞6∫αγ∞7∫αγ∞8∫αγ∞9∫αγ∞0∫α\n"*
+                           "  * γ∞1∫α\n"*
+                           "  * γ∞2∫αγ∞3∫αγ∞4∫αγ∞5∫αγ∞6∫αγ∞7∫αγ∞8∫αγ∞9∫αγ∞0"),
+        ]
+    )
+    @test sprint(show, "text/plain", df) == """
+        8×2 DataFrame
+        │ Row │ A     │ B                                 │
+        │     │ Int64 │ Markdown.MD                       │
+        ├─────┼───────┼───────────────────────────────────┤
+        │ 1   │ 1     │ [DataFrames.jl](http://juliadata… │
+        │ 2   │ 4     │ \$\\frac{x^2}{x^2+y^2}\$             │
+        │ 3   │ 9     │ # Header                          │
+        │ 4   │ 16    │ This is *very*, **very**, very, … │
+        │ 5   │ 25    │                                   │
+        │ 6   │ 36    │ ∫αγ∞1∫αγ∞2∫αγ∞3∫αγ∞4∫αγ∞5∫αγ∞6∫α… │
+        │ 7   │ 49    │ ∫αγ∞1∫αγ∞…                        │
+        │ 8   │ 64    │ ∫αγ∞1∫αγ∞2∫αγ∞3∫αγ∞4∫αγ∞5∫αγ∞6∫α… │"""
+
+    @test sprint(show, "text/csv", df) ==
+        """
+        \"A\",\"B\"
+        1,\"[DataFrames.jl](http://juliadata.github.io/DataFrames.jl)\"
+        4,\"\$\\\\frac{x^2}{x^2+y^2}\$\"
+        9,\"# Header\"
+        16,\"This is *very*, **very**, very, very, very, very, very, very, very long line\"
+        25,\"\"
+        36,\"∫αγ∞1∫αγ∞2∫αγ∞3∫αγ∞4∫αγ∞5∫αγ∞6∫αγ∞7∫αγ∞8∫αγ∞9∫αγ∞0∫αγ∞1∫αγ∞2∫αγ∞3\"
+        49,\"∫αγ∞1∫αγ∞\\n\\n  * 2∫αγ∞3∫αγ∞4\\n  * ∫αγ∞5∫αγ\\n  * ∞6∫αγ∞7∫αγ∞8∫αγ∞9∫αγ∞0\"
+        64,\"∫αγ∞1∫αγ∞2∫αγ∞3∫αγ∞4∫αγ∞5∫αγ∞6∫αγ∞7∫αγ∞8∫αγ∞9∫αγ∞0∫α\\n\\n  * γ∞1∫α\\n  * γ∞2∫αγ∞3∫αγ∞4∫αγ∞5∫αγ∞6∫αγ∞7∫αγ∞8∫αγ∞9∫αγ∞0\"
+        """
+end
+
+@testset "Markdown as HTML" begin
+    df = DataFrame(
+        A=Int64[1,4,9,16,25,36,49,64],
+        B = [
+            md"[DataFrames.jl](http://juliadata.github.io/DataFrames.jl)",
+            md"``\frac{x^2}{x^2+y^2}``",
+            md"# Header",
+            md"This is *very*, **very**, very, very, very, very, very, very, very long line" ,
+            md"",
+            Markdown.parse("∫αγ∞1∫αγ∞2∫αγ∞3∫αγ∞4∫αγ∞5∫αγ∞6∫αγ∞7∫αγ∞8∫αγ∞9∫αγ∞0" *
+                           "∫αγ∞1∫αγ∞2∫αγ∞3∫αγ∞4∫αγ∞5∫αγ∞6∫αγ∞7∫αγ∞8∫αγ∞9∫αγ∞0"),
+            Markdown.parse("∫αγ∞1∫αγ∞2∫αγ∞3∫αγ∞4∫αγ∞5∫αγ∞6∫αγ\n"*
+                           "  * ∞7∫αγ\n"*
+                           "  * ∞8∫αγ\n"*
+                           "  * ∞9∫αγ∞0∫α\nγ∞1∫αγ∞2∫αγ∞3∫αγ∞4∫αγ∞5∫αγ∞6∫αγ∞7∫αγ∞8∫αγ∞9∫αγ∞0"),
+            Markdown.parse("∫αγ∞1∫αγ∞2∫αγ∞3∫αγ∞4∫αγ∞5∫αγ∞6∫αγ∞7∫αγ∞8∫αγ∞9∫αγ∞0∫α\n"*
+                           "  * γ∞1∫α\n"*
+                           "  * γ∞2∫αγ∞3∫αγ∞4∫αγ∞5∫αγ∞6∫αγ∞7∫αγ∞8∫αγ∞9∫αγ∞0"),
+        ]
+    )
+    @test sprint(show,"text/html",df) ==
+        "<table class=\"data-frame\"><thead>" *
+            "<tr><th></th><th>A</th><th>B</th></tr>" *
+            "<tr><th></th><th>Int64</th><th>MD…</th></tr>" *
+        "</thead>" *
+        "<tbody>" * "<p>8 rows × 2 columns</p>" *
+        "<tr><th>1</th><td>1</td><td><div class=\"markdown\">" *
+            "<p><a href=\"http://juliadata.github.io/DataFrames.jl\">DataFrames.jl</a></p>\n</div></td></tr>" *
+        "<tr><th>2</th><td>4</td><td><div class=\"markdown\"><p>&#36;\\frac&#123;x^2&#125;&#123;x^2&#43;y^2&#125;&#36;</p>\n</div></td></tr>" *
+        "<tr><th>3</th><td>9</td><td><div class=\"markdown\"><h1>Header</h1>\n</div></td></tr>" *
+        "<tr><th>4</th><td>16</td><td><div class=\"markdown\">" *
+            "<p>This is <em>very</em>, <strong>very</strong>, very, very, very, very, very, very, very long line</p>\n" *
+        "</div></td></tr>" *
+        "<tr><th>5</th><td>25</td><td><div class=\"markdown\"></div></td></tr>" *
+        "<tr><th>6</th><td>36</td><td><div class=\"markdown\">" *
+            "<p>∫αγ∞1∫αγ∞2∫αγ∞3∫αγ∞4∫αγ∞5∫αγ∞6∫αγ∞7∫αγ∞8∫αγ∞9∫αγ∞0∫αγ∞1∫αγ∞2∫αγ∞3∫αγ∞4∫αγ∞5∫αγ∞6∫αγ∞7∫αγ∞8∫αγ∞9∫αγ∞0</p>\n" *
+        "</div></td></tr>" *
+        "<tr><th>7</th><td>49</td><td><div class=\"markdown\">" *
+            "<p>∫αγ∞1∫αγ∞2∫αγ∞3∫αγ∞4∫αγ∞5∫αγ∞6∫αγ</p>\n<ul>\n<li><p>∞7∫αγ</p>\n</li>\n<li><p>∞8∫αγ</p>\n</li>\n<li><p>∞9∫αγ∞0∫α</p>\n</li>\n</ul>\n<p>γ∞1∫αγ∞2∫αγ∞3∫αγ∞4∫αγ∞5∫αγ∞6∫αγ∞7∫αγ∞8∫αγ∞9∫αγ∞0</p>\n" *
+        "</div></td></tr>" *
+        "<tr><th>8</th><td>64</td><td><div class=\"markdown\">" *
+            "<p>∫αγ∞1∫αγ∞2∫αγ∞3∫αγ∞4∫αγ∞5∫αγ∞6∫αγ∞7∫αγ∞8∫αγ∞9∫αγ∞0∫α</p>" *
+            "\n<ul>\n" *
+                "<li><p>γ∞1∫α</p>\n</li>\n" *
+                "<li><p>γ∞2∫αγ∞3∫αγ∞4∫αγ∞5∫αγ∞6∫αγ∞7∫αγ∞8∫αγ∞9∫αγ∞0</p>\n</li>\n" *
+        "</ul>\n" * "</div></td></tr></tbody></table>"
+end
+
 @testset "empty data frame and DataFrameRow" begin
     df = DataFrame(a = [1,2], b = [1.0, 2.0])