Remove TRY_CATCH_FINALLY_FLAG (#123)

A flag is a waste for this; we can just use a different kind for this
horrible edge case.

Author: c42f

src/expr.jl

@@ -150,19 +150,19 @@ function _to_expr(node::SyntaxNode; iteration_spec=false, need_linenodes=true,
             pushfirst!(args, args[end])
             pop!(args)
         end
-    elseif headsym == :try
+    elseif headsym in (:try, :try_finally_catch)
         # Try children in source order:
         #   try_block catch_var catch_block else_block finally_block
         # Expr ordering:
         #   try_block catch_var catch_block [finally_block] [else_block]
         catch_ = nothing
-        if has_flags(node, TRY_CATCH_AFTER_FINALLY_FLAG)
+        if headsym === :try_finally_catch
             catch_ = pop!(args)
             catch_var = pop!(args)
         end
         finally_ = pop!(args)
         else_ = pop!(args)
-        if has_flags(node, TRY_CATCH_AFTER_FINALLY_FLAG)
+        if headsym === :try_finally_catch
             pop!(args)
             pop!(args)
             push!(args, catch_var)
@@ -176,6 +176,7 @@ function _to_expr(node::SyntaxNode; iteration_spec=false, need_linenodes=true,
         if else_ !== false
             push!(args, else_)
         end
+        headsym = :try
     elseif headsym == :filter
         pushfirst!(args, last(args))
         pop!(args)

src/kinds.jl

@@ -897,6 +897,8 @@ const _kind_names =
         "flatten"
         "comprehension"
         "typed_comprehension"
+        # Special kind for compatibility with the ever-ugly try-finally-catch ordering
+        "try_finally_catch"
     "END_SYNTAX_KINDS"
 ]
 

src/parse_stream.jl

@@ -15,8 +15,6 @@ const DOTOP_FLAG = RawFlags(1<<2)
 const TRIPLE_STRING_FLAG = RawFlags(1<<3)
 # Set when a string or identifier needs "raw string" unescaping
 const RAW_STRING_FLAG = RawFlags(1<<4)
-# try-finally-catch
-const TRY_CATCH_AFTER_FINALLY_FLAG = RawFlags(1<<5)
 # Record whether operator has a suffix
 const SUFFIXED_FLAG        = RawFlags(1<<6)
 
@@ -75,7 +73,6 @@ function untokenize(head::SyntaxHead; unique=true, include_flag_suff=true)
         is_infix(head)   && (str = str*"i")
         has_flags(head, TRIPLE_STRING_FLAG) && (str = str*"s")
         has_flags(head, RAW_STRING_FLAG) && (str = str*"r")
-        has_flags(head, TRY_CATCH_AFTER_FINALLY_FLAG) && (str = str*"f")
         is_suffixed(head) && (str = str*"S")
         n = numeric_flags(head)
         n != 0 && (str = str*string(n))

src/parser.jl

@@ -2085,6 +2085,7 @@ end
 #
 # flisp: embedded in parse_resword
 function parse_try(ps)
+    out_kind = K"try"
     mark = position(ps)
     bump(ps, TRIVIA_FLAG)
     parse_block(ps)
@@ -2132,15 +2133,15 @@ function parse_try(ps)
     # in which these blocks execute.
     bump_trivia(ps)
     if !has_catch && peek(ps) == K"catch"
-        # try x finally y catch e z end  ==>  (try-f (block x) false false false (block y) e (block z))
-        flags |= TRY_CATCH_AFTER_FINALLY_FLAG
+        # try x finally y catch e z end  ==>  (try_finally_catch (block x) false false false (block y) e (block z))
+        out_kind = K"try_finally_catch"
         m = position(ps)
         parse_catch(ps)
         emit_diagnostic(ps, m, position(ps),
                         warning="`catch` after `finally` will execute out of order")
     end
     bump_closing_token(ps, K"end")
-    emit(ps, mark, K"try", flags)
+    emit(ps, mark, out_kind, flags)
 end
 
 function parse_catch(ps::ParseState)

test/parser.jl

@@ -1,13 +1,17 @@
-function test_parse(production, code; v=v"1.6")
+function test_parse(production, code; v=v"1.6", expr=false)
     stream = ParseStream(code, version=v)
     production(ParseState(stream))
     t = build_tree(GreenNode, stream, wrap_toplevel_as_kind=K"None")
     source = SourceFile(code)
     s = SyntaxNode(source, t)
-    if kind(s) == K"None"
-        join([sprint(show, MIME("text/x.sexpression"), c) for c in children(s)], ' ')
+    if expr
+        JuliaSyntax.remove_linenums!(Expr(s))
     else
-        sprint(show, MIME("text/x.sexpression"), s)
+        if kind(s) == K"None"
+            join([sprint(show, MIME("text/x.sexpression"), c) for c in children(s)], ' ')
+        else
+            sprint(show, MIME("text/x.sexpression"), s)
+        end
     end
 end
 
@@ -482,7 +486,8 @@ tests = [
         ((v=v"1.8",), "try else end") => "(try (block) false false (error (block)) false)"
         ((v=v"1.7",), "try catch ; else end")  =>  "(try (block) false (block) (error (block)) false)"
         # finally before catch :-(
-        "try x finally y catch e z end"  =>  "(try-f (block x) false false false (block y) e (block z))"
+        "try x finally y catch e z end"  =>  "(try_finally_catch (block x) false false false (block y) e (block z))" =>
+            Expr(:try, Expr(:block, :x), :e, Expr(:block, :z), Expr(:block, :y))
     ],
     JuliaSyntax.parse_imports => [
         "import A as B: x"  => "(import (: (error (as (. A) B)) (. x)))"
@@ -816,7 +821,12 @@ broken_tests = [
             else
                 opts = NamedTuple()
             end
-            @test test_parse(production, input; opts...) == output
+            if output isa Pair
+                @test test_parse(production, input; opts...) == output[1]
+                @test test_parse(production, input; opts..., expr=true) == output[2]
+            else
+                @test test_parse(production, input; opts...) == output
+            end
         end
     end
     @testset "Broken $production" for (production, test_specs) in broken_tests