Try make REPL error easier to visually parse

base/REPL.jl

@@ -112,14 +112,12 @@ end
 
 function display_error(io::IO, er, bt)
     print_with_color(Base.error_color(), io, "ERROR: "; bold = true)
-    Base.with_output_color(Base.error_color(), io) do io
-        # remove REPL-related frames from interactive printing
-        eval_ind = findlast(addr->ip_matches_func(addr, :eval), bt)
-        if eval_ind != 0
-            bt = bt[1:eval_ind-1]
-        end
-        Base.showerror(IOContext(io, :limit => true), er, bt)
+    # remove REPL-related frames from interactive printing
+    eval_ind = findlast(addr->Base.REPL.ip_matches_func(addr, :eval), bt)
+    if eval_ind != 0
+        bt = bt[1:eval_ind-1]
     end
+    showerror(IOContext(io, :limit => true), er, bt)
 end
 
 immutable REPLDisplay{R<:AbstractREPL} <: Display
@@ -167,6 +165,8 @@ function print_response(errio::IO, val::ANY, bt, show_value::Bool, have_color::B
         catch err
             if bt !== nothing
                 println(errio, "SYSTEM: show(lasterr) caused an error")
+                println(errio, err)
+                Base.show_backtrace(errio, bt)
                 break
             end
             val = err

base/array.jl

@@ -737,7 +737,8 @@ julia> deleteat!([6, 5, 4, 3, 2, 1], 1:2:5)
 
 julia> deleteat!([6, 5, 4, 3, 2, 1], (2, 2))
 ERROR: ArgumentError: indices must be unique and sorted
- in deleteat!(::Array{Int64,1}, ::Tuple{Int64,Int64}) at ./array.jl:753
+Stacktrace:
+ [1] deleteat!(::Array{Int64,1}, ::Tuple{Int64,Int64}) at ./array.jl:748
 ```
 """
 function deleteat!(a::Vector, inds)

base/client.jl

@@ -22,18 +22,19 @@ const text_colors = AnyDict(
     :normal        => "\033[0m",
     :default       => "\033[39m",
     :bold          => "\033[1m",
+    :nothing       => "",
 )
 
+for i in 0:255
+    text_colors[i] = "\033[38;5;$(i)m"
+end
+
 const disable_text_style = AnyDict(
     :bold => "\033[22m",
     :normal => "",
     :default => "",
 )
 
-for i in 0:255
-    text_colors[i] = "\033[38;5;$(i)m"
-end
-
 # Create a docstring with an automatically generated list
 # of colors.
 available_text_colors = collect(Iterators.filter(x -> !isa(x, Integer), keys(text_colors)))
@@ -52,6 +53,7 @@ Available colors are: $available_text_colors_docstring as well as the integers 0
 
 The color `:default` will print text in the default color while the color `:normal`
 will print text with all text properties (like boldness) reset.
+Printing with the color `:nothing` will print the string without modifications.
 """
 text_colors
 
@@ -83,6 +85,9 @@ info_color()  = repl_color("JULIA_INFO_COLOR" , default_color_info)
 input_color()  = text_colors[:bold] * text_colors[repl_color("JULIA_INPUT_COLOR", default_color_input)]
 answer_color() = text_colors[:bold] * text_colors[repl_color("JULIA_ANSWER_COLOR", default_color_answer)]
 
+stackframe_lineinfo_color() = repl_color("JULIA_STACKFRAME_LINEINFO_COLOR", :bold)
+stackframe_function_color() = repl_color("JULIA_STACKFRAME_FUNCTION_COLOR", :bold)
+
 function repl_cmd(cmd, out)
     shell = shell_split(get(ENV,"JULIA_SHELL",get(ENV,"SHELL","/bin/sh")))
     # Note that we can't support the fish shell due to its lack of subshells

base/docs/helpdb/Base.jl

@@ -450,7 +450,8 @@ If `T` is not a bitstype, an error is thrown.
 ```jldoctest
 julia> sizeof(Base.LinAlg.LU)
 ERROR: argument is an abstract type; size is indeterminate
- in sizeof(::Type{T}) at ./essentials.jl:99
+Stacktrace:
+ [1] sizeof(::Type{T}) at ./essentials.jl:99
 ```
 """
 sizeof(::Type)
@@ -2531,7 +2532,8 @@ julia> convert(Int, 3.0)
 
 julia> convert(Int, 3.5)
 ERROR: InexactError()
- in convert(::Type{Int64}, ::Float64) at ./float.jl:656
+Stacktrace:
+ [1] convert(::Type{Int64}, ::Float64) at ./float.jl:656
 ```
 
 If `T` is a `AbstractFloat` or `Rational` type,

base/linalg/eigen.jl

@@ -208,8 +208,9 @@ julia> A = [0 im; -1 0]
 
 julia> eigmax(A)
 ERROR: DomainError:
- in #eigmax#36(::Bool, ::Bool, ::Function, ::Array{Complex{Int64},2}) at ./linalg/eigen.jl:218
- in eigmax(::Array{Complex{Int64},2}) at ./linalg/eigen.jl:216
+Stacktrace:
+ [1] #eigmax#30(::Bool, ::Bool, ::Function, ::Array{Complex{Int64},2}) at ./linalg/eigen.jl:219
+ [2] eigmax(::Array{Complex{Int64},2}) at ./linalg/eigen.jl:217
 ```
 """
 function eigmax(A::Union{Number, StridedMatrix}; permute::Bool=true, scale::Bool=true)
@@ -249,8 +250,9 @@ julia> A = [0 im; -1 0]
 
 julia> eigmin(A)
 ERROR: DomainError:
- in #eigmin#37(::Bool, ::Bool, ::Function, ::Array{Complex{Int64},2}) at ./linalg/eigen.jl:259
- in eigmin(::Array{Complex{Int64},2}) at ./linalg/eigen.jl:257
+Stacktrace:
+ [1] #eigmin#31(::Bool, ::Bool, ::Function, ::Array{Complex{Int64},2}) at ./linalg/eigen.jl:261
+ [2] eigmin(::Array{Complex{Int64},2}) at ./linalg/eigen.jl:259
 ```
 """
 function eigmin(A::Union{Number, StridedMatrix}; permute::Bool=true, scale::Bool=true)

base/nullable.jl

@@ -111,7 +111,8 @@ Nullable{String}()
 
 julia> unsafe_get(x)
 ERROR: UndefRefError: access to undefined reference
- in unsafe_get(::Nullable{String}) at ./nullable.jl:123
+Stacktrace:
+ [1] unsafe_get(::Nullable{String}) at ./nullable.jl:124
 
 julia> x = 1
 1

base/replutil.jl

@@ -194,7 +194,9 @@ end
 
 function showerror(io::IO, ex, bt; backtrace=true)
     try
-        showerror(io, ex)
+        with_output_color(have_color ? error_color() : :nothing, io) do io
+            showerror(io, ex)
+        end
     finally
         backtrace && show_backtrace(io, bt)
     end
@@ -577,15 +579,21 @@ function show_method_candidates(io::IO, ex::MethodError, kwargs::Vector=Any[])
     end
 end
 
-function show_trace_entry(io, frame, n)
+function show_trace_entry(io, frame, n; prefix = " in ")
     print(io, "\n")
-    show(io, frame, full_path=true)
+    show(io, frame, full_path=true; prefix = prefix)
     n > 1 && print(io, " (repeats ", n, " times)")
 end
 
 function show_backtrace(io::IO, t::Vector)
-    process_entry(last_frame, n) =
-        show_trace_entry(io, last_frame, n)
+    n_frames = 0
+    frame_counter = 0
+    process_backtrace((a,b) -> n_frames += 1, t)
+    n_frames != 0 && print(io, "\nStacktrace:")
+    process_entry = (last_frame, n) -> begin
+        frame_counter += 1
+        show_trace_entry(io, last_frame, n, prefix = string(" [", frame_counter, "] "))
+    end
     process_backtrace(process_entry, t)
 end
 

base/show.jl

@@ -1031,31 +1031,37 @@ end
 
 function show_lambda_types(io::IO, li::Core.MethodInstance)
     # print a method signature tuple for a lambda definition
-    if li.specTypes === Tuple
-        print(io, li.def.name, "(...)")
-        return
-    end
-
-    sig = li.specTypes.parameters
-    ft = sig[1]
-    if ft <: Function && isempty(ft.parameters) &&
-            isdefined(ft.name.module, ft.name.mt.name) &&
-            ft == typeof(getfield(ft.name.module, ft.name.mt.name))
-        print(io, ft.name.mt.name)
-    elseif isa(ft, DataType) && ft.name === Type.name && isleaftype(ft)
-        f = ft.parameters[1]
-        print(io, f)
-    else
-        print(io, "(::", ft, ")")
+    local sig
+    returned_from_do = false
+    Base.with_output_color(have_color ? stackframe_function_color() : :nothing, io) do io
+        if li.specTypes === Tuple
+            print(io, li.def.name, "(...)")
+            returned_from_do = true
+            return
+        end
+        sig = li.specTypes.parameters
+        ft = sig[1]
+        if ft <: Function && isempty(ft.parameters) &&
+                isdefined(ft.name.module, ft.name.mt.name) &&
+                ft == typeof(getfield(ft.name.module, ft.name.mt.name))
+            print(io, ft.name.mt.name)
+        elseif isa(ft, DataType) && ft.name === Type.name && isleaftype(ft)
+            f = ft.parameters[1]
+            print(io, f)
+        else
+            print(io, "(::", ft, ")")
+        end
     end
+    returned_from_do && return
     first = true
-    print(io, '(')
+    print_style = have_color ? :bold : :nothing
+    print_with_color(print_style, io, "(")
     for i = 2:length(sig)  # fixme (iter): `eachindex` with offset?
         first || print(io, ", ")
         first = false
         print(io, "::", sig[i])
     end
-    print(io, ')')
+    print_with_color(print_style, io, ")")
     nothing
 end
 

base/stacktraces.jl

@@ -188,7 +188,7 @@ function show_spec_linfo(io::IO, frame::StackFrame)
         if frame.func === empty_sym
             @printf(io, "ip:%#x", frame.pointer)
         else
-            print(io, frame.func)
+            print_with_color(Base.have_color ? Base.stackframe_function_color() : :nothing, io, string(frame.func))
         end
     else
         linfo = get(frame.linfo)
@@ -200,16 +200,20 @@ function show_spec_linfo(io::IO, frame::StackFrame)
     end
 end
 
-function show(io::IO, frame::StackFrame; full_path::Bool=false)
-    print(io, " in ")
+function show(io::IO, frame::StackFrame; full_path::Bool=false,
+              prefix = " in ")
+    print(io, prefix)
     show_spec_linfo(io, frame)
     if frame.file !== empty_sym
         file_info = full_path ? string(frame.file) : basename(string(frame.file))
-        print(io, " at ", file_info, ":")
-        if frame.line >= 0
-            print(io, frame.line)
-        else
-            print(io, "?")
+        print(io, " at ")
+        Base.with_output_color(Base.have_color ? Base.stackframe_lineinfo_color() : :nothing, io) do io
+            print(io, file_info, ":")
+            if frame.line >= 0
+                print(io, frame.line)
+            else
+                print(io, "?")
+            end
         end
     end
     if frame.inlined

base/test.jl

@@ -972,7 +972,8 @@ Body:
 
 julia> @inferred f(1,2,3)
 ERROR: return type Int64 does not match inferred return type Union{Float64,Int64}
- in error(::String) at ./error.jl:21
+Stacktrace:
+ [1] error(::String) at ./error.jl:21
 
 julia> @inferred max(1,2)
 2

base/util.jl

@@ -309,7 +309,7 @@ function with_output_color(f::Function, color::Union{Int, Symbol}, io::IO, args.
     have_color && print(buf, get(text_colors, color, color_normal))
     try f(IOContext(buf, io), args...)
     finally
-        have_color && print(buf, get(disable_text_style, color, text_colors[:default]))
+        have_color && color != :nothing && print(buf, get(disable_text_style, color, text_colors[:default]))
         have_color && (bold || color == :bold) && print(buf, disable_text_style[:bold])
         print(io, String(take!(buf)))
     end

test/cmdlineargs.jl

@@ -366,12 +366,12 @@ end
 for precomp in ("yes", "no")
     bt = readstring(pipeline(ignorestatus(`$(Base.julia_cmd()) --startup-file=no --precompiled=$precomp
         -E 'include("____nonexistent_file")'`), stderr=catcmd))
-    @test contains(bt, "in include_from_node1")
+    @test contains(bt, "include_from_node1")
     if is_windows() && Sys.WORD_SIZE == 32 && precomp == "yes"
         # fixme, issue #17251
-        @test_broken contains(bt, "in include_from_node1(::String) at $(joinpath(".","loading.jl"))")
+        @test_broken contains(bt, "include_from_node1(::String) at $(joinpath(".","loading.jl"))")
     else
-        @test contains(bt, "in include_from_node1(::String) at $(joinpath(".","loading.jl"))")
+        @test contains(bt, "include_from_node1(::String) at $(joinpath(".","loading.jl"))")
     end
     lno = match(r"at \.[\/\\]loading\.jl:(\d+)", bt)
     @test length(lno.captures) == 1

test/compile.jl

@@ -217,7 +217,7 @@ try
           end
           """)
 
-    t = redirected_stderr("ERROR: LoadError: Declaring __precompile__(false) is not allowed in files that are being precompiled.\n in __precompile__")
+    t = redirected_stderr("ERROR: LoadError: Declaring __precompile__(false) is not allowed in files that are being precompiled.\nStacktrace:\n [1] __precompile__")
     try
         Base.compilecache("Baz") # from __precompile__(false)
         error("__precompile__ disabled test failed")
@@ -314,7 +314,7 @@ try
           error("break me")
           end
           """)
-    t = redirected_stderr("ERROR: LoadError: break me\n in error")
+    t = redirected_stderr("ERROR: LoadError: break me\nStacktrace:\n [1] error")
     try
         Base.require(:FooBar)
         error("\"LoadError: break me\" test failed")