update readme + make sure single args don't nest parens,braces,etc

domluna · Apr 8, 2019 · 4e6b9e0 · 4e6b9e0
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diff --git a/.gitignore b/.gitignore
@@ -1 +0,0 @@
-*.jl

diff --git a/README.md b/README.md
@@ -14,18 +14,20 @@ Width-sensitive formatter for Julia code. Inspired by gofmt and refmt.
 `JLFmt` exports a singular function:
 
 ```julia
-format(text::String; indent_width=4, max_width=80)
+format(text::String; indent_size=4, print_width=80)
 ```
 
-* `indent_width` - the number of spaces used for an indentation.
+* `indent_size` - the number of spaces used for an indentation.
 * `print_width` - the maximum number of characters of code on a single line. Lines over
 the limit will be nested if possible.
 
-### How It Works
+## How It Works
 
-`JLFmt` parses the Julia file using [`CSTParser`](https://github.com/ZacLN/CSTParser.jl).
+`JLFmt` parses the `.jl` source file into a Concrete Syntax Tree (CST) using [`CSTParser`](https://github.com/ZacLN/CSTParser.jl).
 
-Next the CST is _prettified_ using `pretty`, creating a `PTree`. The printing output of a `PTree` is a canonical representation of the code removing unnecessary whitespace and joining or separating lines of code. The [`pretty` testset](./test/runtests.jl) displays these transformations.
+### Pass 1: Prettify
+
+The CST is _prettified_ using `pretty`, creating a `PTree`. The printing output of a `PTree` is a canonical representation of the code removing unnecessary whitespace and joining or separating lines of code. The [`pretty` testset](./test/runtests.jl) displays these transformations.
 
 Example 1:
 
@@ -56,12 +58,102 @@ for cond
 end
 ```
 
-Once the `PTree` is created it's then nested using `nest!` to disjoin lines going over the
-maximum width. The `PTree` is modified in-place. All expressions are nested front to back with the exception of binary operations, where operations, and conditionals.
+### Pass 2: Nesting
+
+`PTree` is nested using `nest!` to disjoin lines going over the print width. 
+The `PTree` is modified in-place. All expressions are nested front to back with the exception of binary 
+operations and conditionals.
+
+**Binary Ops**
+
+```julia
+arg1 && arg2
+
+->
+
+arg1 && 
+arg2
+```
+
+```julia
+foo() = body
+
+->
+
+# The indentation of the body is based on `indent_size`
+foo() =
+    body
+```
+
+**Conditionals**
+
+```julia
+cond ? e1 : e2
+
+->
+
+cond ? e1 :
+e2
+
+->
+
+cond ? 
+e1 :
+e2
+```
+
+**Calls** (also applies to {}, (), [], etc)
+
+```julia
+f(arg1, arg2, arg3)
+
+->
+
+f(
+  arg1,
+  arg2,
+  arg3
+)
+```
+
+```julia
+function longfunctionname_that_is_long(lots, of, args, even, more, args)
+    ..code..
+end
+
+->
+
+# The arg is placed `indent_size` spaces after the start of the
+# function name or one space after the opening parenthesis.
+function longfunctionname_that_is_long(
+             lots, 
+             of, 
+             args,
+             even, 
+             more, 
+             args
+         )
+    ..code..
+end
+```
+
+```julia
+S <: Union{Type1,Type2,Type3}
+
+->
+
+S <: Union{
+         Type1,
+         Type2,
+         Type3
+     }
+```
+
+### Part 3: Printing
 
 Finally, the `PTree` to an `IOBuffer` with `print_tree` which is then consumed as a `String`.
 
-### Known Limitations
+### Known Limitation(s)
 
 If a comment is at the end of a line of code it will be removed.
 

diff --git a/src/JLFmt.jl b/src/JLFmt.jl
@@ -29,7 +29,7 @@ function file_line_ranges(text::String)
                 push!(ranges, s:offset+nl)
             end
         elseif t.kind == Tokens.COMMENT
-            #= @info "comment token" t =#
+            # @info "comment token" t
         end
 
         if (t.kind == Tokens.TRIPLE_STRING || t.kind == Tokens.STRING)
@@ -45,7 +45,7 @@ struct Document
     # mapping the offset in the file to the raw literal
     # string and what lines it starts and ends at.
     lit_strings::Dict{Int, Tuple{Int, Int, String}}
-    #= inline_commments::Vector{LitString} =#
+    # inline_commments::Vector{LitString}
 end
 Document(s::String) = Document(s, file_line_ranges(s)...)
 

diff --git a/src/nest.jl b/src/nest.jl
@@ -5,7 +5,7 @@
 # This is done by replacing `Placeholder` nodes with `Newline` 
 # nodes and updating the PTree's indent.
 #
-# `extra_width` provides additional length to consider from
+# `extra_width` provides additional width to consider from
 # the top-level node.
 #
 # Example:
@@ -40,14 +40,15 @@ function nest!(x::PTree, s::State; extra_width=0)
             s.line_offset = x.nodes[i+1].indent
         elseif n === newline
             s.line_offset = x.indent
+        elseif n isa NotCode && x.nodes[i+1] isa PTree{CSTParser.EXPR{CSTParser.Block}}
+            s.line_offset = x.nodes[i+1].indent
         else
             nest!(n, s, extra_width=extra_width)
         end
     end
 end
 
 function nest!(x::PTree{CSTParser.EXPR{T}}, s::State; extra_width=0) where T <: Union{CSTParser.Import,CSTParser.Using,CSTParser.Export}
-    #= @info "ENTER" typeof(x) s.line_offset x =#
     line_width = s.line_offset + length(x) + extra_width
     idx = findfirst(n -> is_placeholder(n), x.nodes)
     if idx !== nothing && line_width > s.print_width
@@ -76,7 +77,6 @@ function nest!(x::PTree{CSTParser.EXPR{T}}, s::State; extra_width=0) where T <:
             end
         end
     end
-    #= @info "EXIT" typeof(x) s.line_offset x =#
 end
 
 # TODO: skip nesting anything in InvisBrackets?
@@ -86,7 +86,6 @@ end
 function nest!(x::PTree{CSTParser.EXPR{T}}, s::State; extra_width=0) where T <: Union{CSTParser.TupleH,CSTParser.Vect,CSTParser.Braces,CSTParser.Parameters}
     line_width = s.line_offset + length(x) + extra_width
     idx = findlast(n -> is_placeholder(n), x.nodes)
-    #= @info "ENTER" typeof(x) s.line_offset line_width =#
     if idx !== nothing && line_width > s.print_width
         line_offset = s.line_offset
         x.indent = is_opener(x.nodes[1]) ? s.line_offset + 1 : s.line_offset
@@ -115,21 +114,12 @@ end
 function nest!(x::PTree{CSTParser.EXPR{T}}, s::State; extra_width=0) where T <: Union{CSTParser.Curly,CSTParser.Call}
     line_width = s.line_offset + length(x) + extra_width
     idx = findlast(n -> is_placeholder(n), x.nodes)
-    # @info "ENTER" typeof(x) s.line_offset line_width extra_width
     if idx !== nothing && line_width > s.print_width
         line_offset = s.line_offset
         name_width = length(x.nodes[1]) + length(x.nodes[2])
         x.indent = s.line_offset + min(name_width, s.indent_size)
 
         for (i, n) in enumerate(x.nodes)
-            # closing punctuation should be aligned with the
-            # call name:
-            #
-            # foo(
-            #     a,
-            #     b,
-            #     c
-            # )
             if n === newline
                 s.line_offset = x.indent
             elseif is_placeholder(n) 
@@ -154,7 +144,6 @@ end
 function nest!(x::PTree{CSTParser.EXPR{CSTParser.MacroCall}}, s::State; extra_width=0)
     line_width = s.line_offset + length(x) + extra_width
     idx = findlast(n -> is_placeholder(n), x.nodes)
-    #= @info "ENTER" typeof(x) s.line_offset line_width extra_width =#
     if idx !== nothing && line_width > s.print_width && !(x.nodes[1] isa PTree{CSTParser.EXPR{CSTParser.GlobalRefDoc}})
         line_offset = s.line_offset
         name_width = length(x.nodes[1]) + length(x.nodes[2])
@@ -184,13 +173,11 @@ function nest!(x::PTree{CSTParser.EXPR{CSTParser.MacroCall}}, s::State; extra_wi
 end
 
 function nest!(x::PTree{CSTParser.WhereOpCall}, s::State; extra_width=0)
-    #= @info "ENTER" typeof(x) s.line_offset x =#
     line_width = s.line_offset + length(x) + extra_width
     if line_width > s.print_width
         line_offset = s.line_offset
         # after "A where "
         idx = findfirst(n -> is_placeholder(n), x.nodes)
-        #= Blens = length.(x.nodes[idx+1:end]) =#
         Blens = remaining_lengths(x.nodes[idx+1:end])
 
         # A, +7 is the length of " where "
@@ -206,7 +193,6 @@ function nest!(x::PTree{CSTParser.WhereOpCall}, s::State; extra_width=0)
         # where B
         over = s.line_offset + Blens[1] > s.print_width
         for (i, n) in enumerate(x.nodes[idx+1:end])
-            @info "" s.line_offset n
             if n === newline
                 s.line_offset = x.indent
             elseif is_placeholder(n) && over
@@ -228,7 +214,6 @@ function nest!(x::PTree{CSTParser.WhereOpCall}, s::State; extra_width=0)
             end
         end
     end
-    #= @info "EXIT" typeof(x) s.line_offset =#
 end
 
 # C ? E1 : E2
@@ -242,7 +227,6 @@ end
 # E1 :
 # E2
 function nest!(x::PTree{CSTParser.ConditionalOpCall}, s::State; extra_width=0)
-    #= @info "ENTER" typeof(x) s.line_offset =#
     line_width = s.line_offset + length(x) + extra_width
     if line_width > s.print_width
         idx1 = findfirst(n -> is_placeholder(n), x.nodes)
@@ -296,7 +280,6 @@ end
 # arg2
 function nest!(x::PTree{T}, s::State; extra_width=0) where T <: Union{CSTParser.BinaryOpCall,CSTParser.BinarySyntaxOpCall}
     # If there's no placeholder the binary call is not nestable
-    #= @info "ENTER" typeof(x) s.line_offset x.indent length(x) =#
     idx = findlast(n -> is_placeholder(n), x.nodes) 
     line_width = s.line_offset + length(x) + extra_width
     if idx !== nothing && line_width > s.print_width

diff --git a/src/pretty.jl b/src/pretty.jl
@@ -213,17 +213,13 @@ function pretty(x::CSTParser.LITERAL, s::State; include_quotes=true)
 
     startline, endline, str = s.doc.lit_strings[s.offset-1]
     s.offset += x.fullspan
-    #= @info "" startline endline include_quotes str =#
 
     if !include_quotes
         idx = startswith(str, "\"\"\"") ? 4 : 2
         str = str[idx:end-idx+1]
-        #= @info "after removing quotes" str =#
         str = strip(str, ' ')
-        #= @info "after stripping surrounding whitespace" str =#
         str[1] == '\n' && (str = str[2:end])
         str[end] == '\n' && (str = str[1:end-1])
-        #= @info "after removing extra newlines" str =#
     end
 
     lines = split(str, "\n")
@@ -239,17 +235,13 @@ end
 function pretty(x::CSTParser.EXPR{CSTParser.StringH}, s::State; include_quotes=true)
     startline, endline, str = s.doc.lit_strings[s.offset-1]
     s.offset += x.fullspan
-    #= @info "" startline endline include_quotes str =#
 
     if !include_quotes
         idx = startswith(str, "\"\"\"") ? 4 : 2
         str = str[idx:end-idx+1]
-        #= @info "after removing quotes" str =#
         str = strip(str, ' ')
-        #= @info "after stripping surrounding whitespace" str =#
         str[1] == '\n' && (str = str[2:end])
         str[end] == '\n' && (str = str[1:end-1])
-        #= @info "after removing extra newlines" str =#
     end
 
     lines = split(str, "\n")
@@ -636,12 +628,13 @@ function pretty(x::CSTParser.WhereOpCall, s::State)
     # Used to mark where `B` starts.
     add_node!(t, placeholder)
 
+    multi_arg = length(CSTParser.get_where_params(x)) > 1
     for a in x.args
         n = pretty(a, s)
-        if is_opener(n)
+        if is_opener(n) && multi_arg
             add_node!(t, n, join_lines=true)
             add_node!(t, placeholder)
-        elseif is_closer(n)
+        elseif is_closer(n) && multi_arg
             add_node!(t, placeholder)
             add_node!(t, n, join_lines=true)
         elseif CSTParser.is_comma(a)
@@ -690,11 +683,15 @@ function pretty(x::CSTParser.EXPR{T}, s::State) where T <: Union{CSTParser.Curly
     add_node!(t, pretty(x.args[2], s), join_lines=true)
 
     curly = x isa CSTParser.EXPR{CSTParser.Curly}
-    no_args = length(x.args) < 4
+    if curly
+        multi_arg = length(CSTParser.get_curly_params(x)) > 1
+    else
+        multi_arg = length(CSTParser.get_args(x)) > 1
+    end
 
-    !no_args && (add_node!(t, placeholder))
+    multi_arg && (add_node!(t, placeholder))
     for (i, a) in enumerate(x.args[3:end])
-        if i + 2 == length(x) && !no_args
+        if i + 2 == length(x) && multi_arg
             add_node!(t, placeholder)
             add_node!(t, pretty(a, s), join_lines=true)
         elseif CSTParser.is_comma(a) && i < length(x) - 3 && !(x.args[i+1] isa CSTParser.PUNCTUATION)
@@ -718,14 +715,14 @@ end
 function pretty(x::CSTParser.EXPR{T}, s::State) where T <: Union{CSTParser.TupleH,CSTParser.Braces,CSTParser.Vect}
     t = PTree(x, nspaces(s))
     braces = CSTParser.is_lbrace(x.args[1])
-    no_args = length(x.args) < 3
+    multi_arg = length(x.args) > 4
 
     for (i, a) in enumerate(x)
         n = pretty(a, s)
-        if is_opener(n) && !no_args
+        if is_opener(n) && multi_arg
             add_node!(t, n, join_lines=true)
             add_node!(t, placeholder)
-        elseif is_closer(n) && !no_args
+        elseif is_closer(n) && multi_arg
             add_node!(t, placeholder)
             add_node!(t, n, join_lines=true)
         elseif CSTParser.is_comma(a) && i < length(x) && !(x.args[i+1] isa CSTParser.PUNCTUATION)