errorshow.jl
# This file is a part of Julia. License is MIT: https://julialang.org/license
"""
showerror(io, e)
Show a descriptive representation of an exception object `e`.
This method is used to display the exception after a call to [`throw`](@ref).
# Examples
```jldoctest
julia> struct MyException <: Exception
msg::AbstractString
end
julia> function Base.showerror(io::IO, err::MyException)
print(io, "MyException: ")
print(io, err.msg)
end
julia> err = MyException("test exception")
MyException("test exception")
julia> sprint(showerror, err)
"MyException: test exception"
julia> throw(MyException("test exception"))
ERROR: MyException: test exception
```
"""
showerror(io::IO, ex) = show(io, ex)
"""
register_error_hint(handler, exceptiontype)
Register a "hinting" function `handler(io, exception)` that can
suggest potential ways for users to circumvent errors. `handler`
should examine `exception` to see whether the conditions appropriate
for a hint are met, and if so generate output to `io`.
Packages should call `register_error_hint` from within their
`__init__` function.
For specific exception types, `handler` is required to accept additional arguments:
- `MethodError`: provide `handler(io, exc::MethodError, argtypes, kwargs)`,
which splits the combined arguments into positional and keyword arguments.
When issuing a hint, the output should typically start with `\\n`.
If you define custom exception types, your `showerror` method can
support hints by calling [`show_error_hints`](@ref).
# Example
```
julia> module Hinter
only_int(x::Int) = 1
any_number(x::Number) = 2
function __init__()
register_error_hint(MethodError) do io, exc, argtypes, kwargs
if exc.f == only_int
# Color is not necessary, this is just to show it's possible.
print(io, "\\nDid you mean to call ")
printstyled(io, "`any_number`?", color=:cyan)
end
end
end
end
```
Then if you call `Hinter.only_int` on something that isn't an `Int` (thereby triggering a `MethodError`), it issues the hint:
```
julia> Hinter.only_int(1.0)
ERROR: MethodError: no method matching only_int(::Float64)
Did you mean to call `any_number`?
Closest candidates are:
...
```
!!! compat "Julia 1.5"
Custom error hints are available as of Julia 1.5.
"""
function register_error_hint(handler, exct::Type)
list = get!(()->[], _hint_handlers, exct)
push!(list, handler)
return nothing
end
const _hint_handlers = IdDict{Type,Vector{Any}}()
"""
show_error_hints(io, ex, args...)
Invoke all handlers from [`register_error_hint`](@ref) for the particular
exception type `typeof(ex)`. `args` must contain any other arguments expected by
the handler for that type.
"""
function show_error_hints(io, ex, args...)
hinters = get!(()->[], _hint_handlers, typeof(ex))
for handler in hinters
try
Base.invokelatest(handler, io, ex, args...)
catch err
tn = typeof(handler).name
@error "Hint-handler $handler for $(typeof(ex)) in $(tn.module) caused an error"
end
end
end
function showerror(io::IO, ex::BoundsError)
print(io, "BoundsError")
if isdefined(ex, :a)
print(io, ": attempt to access ")
summary(io, ex.a)
if isdefined(ex, :i)
!isa(ex.a, AbstractArray) && print(io, "\n ")
print(io, " at index [")
if isa(ex.i, AbstractRange)
print(io, ex.i)
else
join(io, ex.i, ", ")
end
print(io, ']')
end
end
show_error_hints(io, ex)
end
function showerror(io::IO, ex::TypeError)
print(io, "TypeError: ")
if ex.expected === Bool
print(io, "non-boolean (", typeof(ex.got), ") used in boolean context")
else
if isvarargtype(ex.got)
targs = (ex.got,)
elseif isa(ex.got, Type)
targs = ("Type{", ex.got, "}")
else
targs = ("a value of type $(typeof(ex.got))",)
end
if ex.context == ""
ctx = "in $(ex.func)"
elseif ex.func === Symbol("keyword argument")
ctx = "in keyword argument $(ex.context)"
else
ctx = "in $(ex.func), in $(ex.context)"
end
print(io, ctx, ", expected ", ex.expected, ", got ", targs...)
end
show_error_hints(io, ex)
end
function showerror(io::IO, ex, bt; backtrace=true)
try
with_output_color(get(io, :color, false) ? error_color() : :nothing, io) do io
showerror(io, ex)
end
finally
backtrace && show_backtrace(io, bt)
end
end
function showerror(io::IO, ex::LoadError, bt; backtrace=true)
print(io, "LoadError: ")
showerror(io, ex.error, bt, backtrace=backtrace)
print(io, "\nin expression starting at $(ex.file):$(ex.line)")
end
showerror(io::IO, ex::LoadError) = showerror(io, ex, [])
function showerror(io::IO, ex::InitError, bt; backtrace=true)
print(io, "InitError: ")
showerror(io, ex.error, bt, backtrace=backtrace)
print(io, "\nduring initialization of module ", ex.mod)
end
showerror(io::IO, ex::InitError) = showerror(io, ex, [])
function showerror(io::IO, ex::DomainError)
if isa(ex.val, AbstractArray)
compact = get(io, :compact, true)
limit = get(io, :limit, true)
print(IOContext(io, :compact => compact, :limit => limit),
"DomainError with ", ex.val)
else
print(io, "DomainError with ", ex.val)
end
if isdefined(ex, :msg)
print(io, ":\n", ex.msg)
end
show_error_hints(io, ex)
nothing
end
function showerror(io::IO, ex::SystemError)
if @static(Sys.iswindows() ? ex.extrainfo isa WindowsErrorInfo : false)
errstring = Libc.FormatMessage(ex.extrainfo.errnum)
extrainfo = ex.extrainfo.extrainfo
else
errstring = Libc.strerror(ex.errnum)
extrainfo = ex.extrainfo
end
if extrainfo === nothing
print(io, "SystemError: $(ex.prefix): ", errstring)
else
print(io, "SystemError (with $extrainfo): $(ex.prefix): ", errstring)
end
end
showerror(io::IO, ::DivideError) = print(io, "DivideError: integer division error")
showerror(io::IO, ::StackOverflowError) = print(io, "StackOverflowError:")
showerror(io::IO, ::UndefRefError) = print(io, "UndefRefError: access to undefined reference")
showerror(io::IO, ::EOFError) = print(io, "EOFError: read end of file")
function showerror(io::IO, ex::ErrorException)
print(io, ex.msg)
if ex.msg == "type String has no field data"
println(io)
print(io, "Use `codeunits(str)` instead.")
end
end
showerror(io::IO, ex::KeyError) = (print(io, "KeyError: key ");
show(io, ex.key);
print(io, " not found"))
showerror(io::IO, ex::InterruptException) = print(io, "InterruptException:")
showerror(io::IO, ex::ArgumentError) = print(io, "ArgumentError: ", ex.msg)
showerror(io::IO, ex::AssertionError) = print(io, "AssertionError: ", ex.msg)
showerror(io::IO, ex::OverflowError) = print(io, "OverflowError: ", ex.msg)
showerror(io::IO, ex::UndefKeywordError) =
print(io, "UndefKeywordError: keyword argument $(ex.var) not assigned")
function showerror(io::IO, ex::UndefVarError)
if ex.var in [:UTF16String, :UTF32String, :WString, :utf16, :utf32, :wstring, :RepString]
return showerror(io, ErrorException("""
`$(ex.var)` has been moved to the package LegacyStrings.jl:
Run Pkg.add("LegacyStrings") to install LegacyStrings on Julia v0.5-;
Then do `using LegacyStrings` to get `$(ex.var)`.
"""))
end
print(io, "UndefVarError: $(ex.var) not defined")
end
function showerror(io::IO, ex::InexactError)
print(io, "InexactError: ", ex.func, '(')
nameof(ex.T) === ex.func || print(io, ex.T, ", ")
print(io, ex.val, ')')
show_error_hints(io, ex)
end
typesof(args...) = Tuple{Any[ Core.Typeof(a) for a in args ]...}
function print_with_compare(io::IO, @nospecialize(a::DataType), @nospecialize(b::DataType), color::Symbol)
if a.name === b.name
Base.show_type_name(io, a.name)
n = length(a.parameters)
print(io, '{')
for i = 1:n
if i > length(b.parameters)
printstyled(io, a.parameters[i], color=color)
else
print_with_compare(io::IO, a.parameters[i], b.parameters[i], color)
end
i < n && print(io, ',')
end
print(io, '}')
else
printstyled(io, a; color=color)
end
end
function print_with_compare(io::IO, @nospecialize(a), @nospecialize(b), color::Symbol)
if a === b
print(io, a)
else
printstyled(io, a; color=color)
end
end
function show_convert_error(io::IO, ex::MethodError, @nospecialize(arg_types_param))
# See #13033
T = striptype(ex.args[1])
if T === nothing
print(io, "First argument to `convert` must be a Type, got ", ex.args[1])
else
print_one_line = isa(T, DataType) && isa(arg_types_param[2], DataType) && T.name != arg_types_param[2].name
printstyled(io, "Cannot `convert` an object of type ")
print_one_line || printstyled(io, "\n ")
print_with_compare(io, arg_types_param[2], T, :light_green)
printstyled(io, " to an object of type ")
print_one_line || printstyled(io, "\n ")
print_with_compare(io, T, arg_types_param[2], :light_red)
end
end
function showerror(io::IO, ex::MethodError)
# ex.args is a tuple type if it was thrown from `invoke` and is
# a tuple of the arguments otherwise.
is_arg_types = isa(ex.args, DataType)
arg_types = is_arg_types ? ex.args : typesof(ex.args...)
f = ex.f
meth = methods_including_ambiguous(f, arg_types)
if length(meth) > 1
return showerror_ambiguous(io, meth, f, arg_types)
end
arg_types_param::SimpleVector = arg_types.parameters
print(io, "MethodError: ")
ft = typeof(f)
name = ft.name.mt.name
f_is_function = false
kwargs = ()
if endswith(string(ft.name.name), "##kw")
f = ex.args[2]
ft = typeof(f)
name = ft.name.mt.name
arg_types_param = arg_types_param[3:end]
kwargs = pairs(ex.args[1])
ex = MethodError(f, ex.args[3:end])
end
if f === Base.convert && length(arg_types_param) == 2 && !is_arg_types
f_is_function = true
show_convert_error(io, ex, arg_types_param)
elseif isempty(methods(f)) && isa(f, DataType) && f.abstract
print(io, "no constructors have been defined for ", f)
elseif isempty(methods(f)) && !isa(f, Function) && !isa(f, Type)
print(io, "objects of type ", ft, " are not callable")
else
if ft <: Function && isempty(ft.parameters) &&
isdefined(ft.name.module, name) &&
ft == typeof(getfield(ft.name.module, name))
f_is_function = true
print(io, "no method matching ", name)
elseif isa(f, Type)
print(io, "no method matching ", f)
else
print(io, "no method matching (::", ft, ")")
end
print(io, "(")
for (i, typ) in enumerate(arg_types_param)
print(io, "::", typ)
i == length(arg_types_param) || print(io, ", ")
end
if !isempty(kwargs)
print(io, "; ")
for (i, (k, v)) in enumerate(kwargs)
print(io, k, "=")
show(IOContext(io, :limit => true), v)
i == length(kwargs) || print(io, ", ")
end
end
print(io, ")")
end
# catch the two common cases of element-wise addition and subtraction
if (f === Base.:+ || f === Base.:-) && length(arg_types_param) == 2
# we need one array of numbers and one number, in any order
if any(x -> x <: AbstractArray{<:Number}, arg_types_param) &&
any(x -> x <: Number, arg_types_param)
nouns = Dict(
Base.:+ => "addition",
Base.:- => "subtraction",
)
varnames = ("scalar", "array")
first, second = arg_types_param[1] <: Number ? varnames : reverse(varnames)
print(io, "\nFor element-wise $(nouns[f]), use broadcasting with dot syntax: $first .$f $second")
end
end
if ft <: AbstractArray
print(io, "\nUse square brackets [] for indexing an Array.")
end
# Check for local functions that shadow methods in Base
if f_is_function && isdefined(Base, name)
basef = getfield(Base, name)
if basef !== ex.f && hasmethod(basef, arg_types)
print(io, "\nYou may have intended to import ")
show_unquoted(io, Expr(:., :Base, QuoteNode(name)))
end
end
if (ex.world != typemax(UInt) && hasmethod(ex.f, arg_types) &&
!hasmethod(ex.f, arg_types, world = ex.world))
curworld = get_world_counter()
print(io, "\nThe applicable method may be too new: running in world age $(ex.world), while current world is $(curworld).")
end
if !is_arg_types
# Check for row vectors used where a column vector is intended.
vec_args = []
hasrows = false
for arg in ex.args
isrow = isa(arg,Array) && ndims(arg)==2 && size(arg,1)==1
hasrows |= isrow
push!(vec_args, isrow ? vec(arg) : arg)
end
if hasrows && applicable(f, vec_args...)
print(io, "\n\nYou might have used a 2d row vector where a 1d column vector was required.",
"\nNote the difference between 1d column vector [1,2,3] and 2d row vector [1 2 3].",
"\nYou can convert to a column vector with the vec() function.")
end
end
show_error_hints(io, ex, arg_types_param, kwargs)
try
show_method_candidates(io, ex, kwargs)
catch ex
@error "Error showing method candidates, aborted" exception=ex,catch_backtrace()
end
end
striptype(::Type{T}) where {T} = T
striptype(::Any) = nothing
function showerror_ambiguous(io::IO, meth, f, args)
print(io, "MethodError: ", f, "(")
p = args.parameters
for (i,a) in enumerate(p)
print(io, "::", a)
i < length(p) && print(io, ", ")
end
print(io, ") is ambiguous. Candidates:")
sigfix = Any
for m in meth
print(io, "\n ", m)
sigfix = typeintersect(m.sig, sigfix)
end
if isa(unwrap_unionall(sigfix), DataType) && sigfix <: Tuple
if all(m->morespecific(sigfix, m.sig), meth)
print(io, "\nPossible fix, define\n ")
Base.show_tuple_as_call(io, :function, sigfix)
else
println(io)
print(io, "To resolve the ambiguity, try making one of the methods more specific, or ")
print(io, "adding a new method more specific than any of the existing applicable methods.")
end
end
nothing
end
#Show an error by directly calling jl_printf.
#Useful in Base submodule __init__ functions where stderr isn't defined yet.
function showerror_nostdio(err, msg::AbstractString)
stderr_stream = ccall(:jl_stderr_stream, Ptr{Cvoid}, ())
ccall(:jl_printf, Cint, (Ptr{Cvoid},Cstring), stderr_stream, msg)
ccall(:jl_printf, Cint, (Ptr{Cvoid},Cstring), stderr_stream, ":\n")
ccall(:jl_static_show, Csize_t, (Ptr{Cvoid},Any), stderr_stream, err)
ccall(:jl_printf, Cint, (Ptr{Cvoid},Cstring), stderr_stream, "\n")
end
function show_method_candidates(io::IO, ex::MethodError, @nospecialize kwargs=())
is_arg_types = isa(ex.args, DataType)
arg_types = is_arg_types ? ex.args : typesof(ex.args...)
arg_types_param = Any[arg_types.parameters...]
# Displays the closest candidates of the given function by looping over the
# functions methods and counting the number of matching arguments.
f = ex.f
ft = typeof(f)
lines = []
# These functions are special cased to only show if first argument is matched.
special = f in [convert, getindex, setindex!]
funcs = Any[(f, arg_types_param)]
# An incorrect call method produces a MethodError for convert.
# It also happens that users type convert when they mean call. So
# pool MethodErrors for these two functions.
if f === convert && !isempty(arg_types_param)
at1 = arg_types_param[1]
if isa(at1,DataType) && (at1::DataType).name === Type.body.name && !Core.Compiler.has_free_typevars(at1)
push!(funcs, (at1.parameters[1], arg_types_param[2:end]))
end
end
for (func, arg_types_param) in funcs
for method in methods(func)
buf = IOBuffer()
iob0 = iob = IOContext(buf, io)
tv = Any[]
sig0 = method.sig
while isa(sig0, UnionAll)
push!(tv, sig0.var)
iob = IOContext(iob, :unionall_env => sig0.var)
sig0 = sig0.body
end
s1 = sig0.parameters[1]
sig = sig0.parameters[2:end]
print(iob, " ")
if !isa(func, rewrap_unionall(s1, method.sig))
# function itself doesn't match
continue
else
# TODO: use the methodshow logic here
use_constructor_syntax = isa(func, Type)
print(iob, use_constructor_syntax ? func : typeof(func).name.mt.name)
end
print(iob, "(")
t_i = copy(arg_types_param)
right_matches = 0
for i = 1 : min(length(t_i), length(sig))
i > 1 && print(iob, ", ")
# If isvarargtype then it checks whether the rest of the input arguments matches
# the varargtype
if Base.isvarargtype(sig[i])
sigstr = (unwrap_unionall(sig[i]).parameters[1], "...")
j = length(t_i)
else
sigstr = (sig[i],)
j = i
end
# Checks if the type of arg 1:i of the input intersects with the current method
t_in = typeintersect(rewrap_unionall(Tuple{sig[1:i]...}, method.sig),
rewrap_unionall(Tuple{t_i[1:j]...}, method.sig))
# If the function is one of the special cased then it should break the loop if
# the type of the first argument is not matched.
t_in === Union{} && special && i == 1 && break
if t_in === Union{}
if get(io, :color, false)
Base.with_output_color(Base.error_color(), iob) do iob
print(iob, "::", sigstr...)
end
else
print(iob, "!Matched::", sigstr...)
end
# If there is no typeintersect then the type signature from the method is
# inserted in t_i this ensures if the type at the next i matches the type
# signature then there will be a type intersect
t_i[i] = sig[i]
else
right_matches += j==i ? 1 : 0
print(iob, "::", sigstr...)
end
end
special && right_matches == 0 && continue
if length(t_i) > length(sig) && !isempty(sig) && Base.isvarargtype(sig[end])
# It ensures that methods like f(a::AbstractString...) gets the correct
# number of right_matches
for t in arg_types_param[length(sig):end]
if t <: rewrap_unionall(unwrap_unionall(sig[end]).parameters[1], method.sig)
right_matches += 1
end
end
end
if right_matches > 0 || length(arg_types_param) < 2
if length(t_i) < length(sig)
# If the methods args is longer than input then the method
# arguments is printed as not a match
for (k, sigtype) in enumerate(sig[length(t_i)+1:end])
sigtype = isvarargtype(sigtype) ? unwrap_unionall(sigtype) : sigtype
if Base.isvarargtype(sigtype)
sigstr = (sigtype.parameters[1], "...")
else
sigstr = (sigtype,)
end
if !((min(length(t_i), length(sig)) == 0) && k==1)
print(iob, ", ")
end
if get(io, :color, false)
Base.with_output_color(Base.error_color(), iob) do iob
print(iob, "::", sigstr...)
end
else
print(iob, "!Matched::", sigstr...)
end
end
end
kwords = kwarg_decl(method)
if !isempty(kwords)
print(iob, "; ")
join(iob, kwords, ", ")
end
print(iob, ")")
show_method_params(iob0, tv)
print(iob, " at ", method.file, ":", method.line)
if !isempty(kwargs)
unexpected = Symbol[]
if isempty(kwords) || !(any(endswith(string(kword), "...") for kword in kwords))
for (k, v) in kwargs
if !(k in kwords)
push!(unexpected, k)
end
end
end
if !isempty(unexpected)
Base.with_output_color(Base.error_color(), iob) do iob
plur = length(unexpected) > 1 ? "s" : ""
print(iob, " got unsupported keyword argument$plur \"", join(unexpected, "\", \""), "\"")
end
end
end
if ex.world < reinterpret(UInt, method.primary_world)
print(iob, " (method too new to be called from this world context.)")
elseif ex.world > reinterpret(UInt, method.deleted_world)
print(iob, " (method deleted before this world age.)")
end
# TODO: indicate if it's in the wrong world
push!(lines, (buf, right_matches))
end
end
end
if !isempty(lines) # Display up to three closest candidates
Base.with_output_color(:normal, io) do io
print(io, "\nClosest candidates are:")
sort!(lines, by = x -> -x[2])
i = 0
for line in lines
println(io)
if i >= 3
print(io, " ...")
break
end
i += 1
print(io, String(take!(line[1])))
end
end
end
end
# Contains file name and file number. Gets set when a backtrace
# or methodlist is shown. Used by the REPL to make it possible to open
# the location of a stackframe/method in the editor.
global LAST_SHOWN_LINE_INFOS = Tuple{String, Int}[]
function show_trace_entry(io, frame, n; prefix = "")
push!(LAST_SHOWN_LINE_INFOS, (string(frame.file), frame.line))
print(io, "\n", prefix)
show(io, frame, full_path=true)
n > 1 && print(io, " (repeats ", n, " times)")
end
# In case the line numbers in the source code have changed since the code was compiled,
# allow packages to set a callback function that corrects them.
# (Used by Revise and perhaps other packages.)
#
# Set this with
# Base.update_stackframes_callback[] = my_updater!
# where my_updater! takes a single argument and works in-place. The argument will be a
# Vector{Any} storing tuples (sf::StackFrame, nrepetitions::Int), and the updater should
# replace `sf` as needed.
const update_stackframes_callback = Ref{Function}(identity)
const BIG_STACKTRACE_SIZE = 50 # Arbitrary constant chosen here
function show_reduced_backtrace(io::IO, t::Vector, with_prefix::Bool)
recorded_positions = IdDict{UInt, Vector{Int}}()
#= For each frame of hash h, recorded_positions[h] is the list of indices i
such that hash(t[i-1]) == h, ie the list of positions in which the
frame appears just before. =#
displayed_stackframes = []
repeated_cycle = Tuple{Int,Int,Int}[]
# First: line to introuce the "cycle repetition" message
# Second: length of the cycle
# Third: number of repetitions
frame_counter = 1
while frame_counter < length(t)
(last_frame, n) = t[frame_counter]
frame_counter += 1 # Indicating the next frame
current_hash = hash(last_frame)
positions = get(recorded_positions, current_hash, Int[])
recorded_positions[current_hash] = push!(positions, frame_counter)
repetitions = 0
for index_p in length(positions)-1:-1:1 # More recent is more likely
p = positions[index_p]
cycle_length = frame_counter - p
i = frame_counter
j = p
while i < length(t) && t[i] == t[j]
i += 1
j += 1
end
if j >= frame_counter-1
#= At least one cycle repeated =#
repetitions = div(i - frame_counter + 1, cycle_length)
push!(repeated_cycle, (length(displayed_stackframes), cycle_length, repetitions))
frame_counter += cycle_length * repetitions - 1
break
end
end
if repetitions==0
push!(displayed_stackframes, (last_frame, n))
end
end
try invokelatest(update_stackframes_callback[], displayed_stackframes) catch end
push!(repeated_cycle, (0,0,0)) # repeated_cycle is never empty
frame_counter = 1
for i in 1:length(displayed_stackframes)
(frame, n) = displayed_stackframes[i]
if with_prefix
show_trace_entry(io, frame, n, prefix = string(" [", frame_counter, "] "))
else
show_trace_entry(io, frame, n)
end
while repeated_cycle[1][1] == i # never empty because of the initial (0,0,0)
cycle_length = repeated_cycle[1][2]
repetitions = repeated_cycle[1][3]
popfirst!(repeated_cycle)
print(io, "\n ... (the last ", cycle_length, " lines are repeated ",
repetitions, " more time", repetitions>1 ? "s)" : ")")
frame_counter += cycle_length * repetitions
end
frame_counter += 1
end
end
function show_backtrace(io::IO, t::Vector)
resize!(LAST_SHOWN_LINE_INFOS, 0)
filtered = process_backtrace(t)
isempty(filtered) && return
if length(filtered) == 1 && StackTraces.is_top_level_frame(filtered[1][1])
f = filtered[1][1]
if f.line == 0 && f.file == Symbol("")
# don't show a single top-level frame with no location info
return
end
end
print(io, "\nStacktrace:")
if length(filtered) < BIG_STACKTRACE_SIZE
# Fast track: no duplicate stack frame detection.
try invokelatest(update_stackframes_callback[], filtered) catch end
frame_counter = 0
for (last_frame, n) in filtered
frame_counter += 1
show_trace_entry(IOContext(io, :backtrace => true), last_frame, n, prefix = string(" [", frame_counter, "] "))
end
return
end
show_reduced_backtrace(IOContext(io, :backtrace => true), filtered, true)
end
function show_backtrace(io::IO, t::Vector{Any})
# t is a pre-processed backtrace (ref #12856)
if length(t) < BIG_STACKTRACE_SIZE
try invokelatest(update_stackframes_callback[], t) catch end
for entry in t
show_trace_entry(io, entry...)
end
else
show_reduced_backtrace(io, t, false)
end
end
function is_kw_sorter_name(name::Symbol)
sn = string(name)
return !startswith(sn, '#') && endswith(sn, "##kw")
end
function process_backtrace(t::Vector, limit::Int=typemax(Int); skipC = true)
n = 0
last_frame = StackTraces.UNKNOWN
count = 0
ret = Any[]
for i in eachindex(t)
lkups = t[i]
if lkups isa StackFrame
lkups = [lkups]
else
lkups = StackTraces.lookup(lkups)
end
for lkup in lkups
if lkup === StackTraces.UNKNOWN
continue
end
if (lkup.from_c && skipC) || is_kw_sorter_name(lkup.func)
continue
end
count += 1
if count > limit
break
end
if lkup.file != last_frame.file || lkup.line != last_frame.line || lkup.func != last_frame.func || lkup.linfo !== lkup.linfo
if n > 0
push!(ret, (last_frame, n))
end
n = 1
last_frame = lkup
else
n += 1
end
end
count > limit && break
end
if n > 0
push!(ret, (last_frame, n))
end
return ret
end
function show_exception_stack(io::IO, stack::Vector)
# Display exception stack with the top of the stack first. This ordering
# means that the user doesn't have to scroll up in the REPL to discover the
# root cause.
nexc = length(stack)
for i = nexc:-1:1
if nexc != i
printstyled(io, "caused by [exception ", i, "]\n", color=:light_black)
end
exc, bt = stack[i]
showerror(io, exc, bt, backtrace = bt!==nothing)
println(io)
end
end
# Defined here rather than error.jl for bootstrap ordering
function show(io::IO, ip::InterpreterIP)
print(io, typeof(ip))
if ip.code isa Core.CodeInfo
print(io, " in top-level CodeInfo for $(ip.mod) at statement $(Int(ip.stmt))")
else
print(io, " in $(ip.code) at statement $(Int(ip.stmt))")
end
end
