Some robustness improvements (#69)

* Check funcdef expressions and give up faster

* Check for existence of file before trying to load the source

Author: timholy

Project.toml

@@ -13,7 +13,8 @@ julia = "1"
 [extras]
 ColorTypes = "3da002f7-5984-5a60-b8a6-cbb66c0b333f"
 LinearAlgebra = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"
+SparseArrays = "2f01184e-e22b-5df5-ae63-d93ebab69eaf"
 Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
 
 [targets]
-test = ["ColorTypes", "LinearAlgebra", "Test"]
+test = ["ColorTypes", "LinearAlgebra", "SparseArrays", "Test"]

src/CodeTracking.jl

@@ -206,6 +206,7 @@ function definition(::Type{String}, method::Method)
     file, line = whereis(method)
     line == 0 && return nothing
     src = src_from_file_or_REPL(file)
+    src === nothing && return nothing
     src = replace(src, "\r"=>"")
     eol = isequal('\n')
     linestarts = Int[]
@@ -222,7 +223,8 @@ function definition(::Type{String}, method::Method)
     end
     # The function declaration was presumably on a previous line
     lineindex = lastindex(linestarts)
-    while !isfuncexpr(ex, method.name) && lineindex > 0
+    linestop = max(0, lineindex - 20)
+    while !isfuncexpr(ex, method.name) && lineindex > linestop
         istart = linestarts[lineindex]
         try
             ex, iend = Meta.parse(src, istart)
@@ -231,6 +233,7 @@ function definition(::Type{String}, method::Method)
         lineindex -= 1
         line -= 1
     end
+    lineindex <= linestop && return nothing
     return chomp(src[istart:iend-1]), line
 end
 

src/utils.jl

@@ -7,6 +7,7 @@ function checkname(fdef::Expr, name)
         # E.g. `function Mod.bar.foo(a, b)`
         return checkname(fproto.args[end], name)
     end
+    isa(fproto, Symbol) || isa(fproto, QuoteNode) || isa(fproto, Expr) || return false
     return checkname(fproto, name)
 end
 checkname(fname::Symbol, name::Symbol) = begin
@@ -75,6 +76,7 @@ function src_from_file_or_REPL(origin::AbstractString, args...)
     if m !== nothing
         return src_from_REPL(m.captures[1], args...)
     end
+    isfile(origin) || return nothing
     return read(origin, String)
 end
 

test/Project.toml

@@ -2,4 +2,5 @@
 ColorTypes = "3da002f7-5984-5a60-b8a6-cbb66c0b333f"
 InteractiveUtils = "b77e0a4c-d291-57a0-90e8-8db25a27a240"
 LinearAlgebra = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"
+SparseArrays = "2f01184e-e22b-5df5-ae63-d93ebab69eaf"
 Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"

test/runtests.jl

@@ -1,7 +1,7 @@
 # Note: some of CodeTracking's functionality can only be tested by Revise
 
 using CodeTracking
-using Test, InteractiveUtils, LinearAlgebra
+using Test, InteractiveUtils, LinearAlgebra, SparseArrays
 # Note: ColorTypes needs to be installed, but note the intentional absence of `using ColorTypes`
 
 using CodeTracking: line_is_decl
@@ -127,6 +127,17 @@ isdefined(Main, :Revise) ? Main.Revise.includet("script.jl") : include("script.j
     B = Hermitian(hcat([one(BigFloat) + im]))
     m = @which cholesky(B)
     @test startswith(definition(String, m)[1], "cholesky")
+
+    # Ensure that we don't error on difficult cases
+    m = which(+, (AbstractSparseVector, AbstractSparseVector))  # defined inside an `@eval`
+    d = definition(String, m)
+    @test d === nothing || isa(d[1], String)
+
+    # Check for existence of file
+    id = Base.PkgId("__PackagePrecompilationStatementModule")
+    mod = Base.root_module(id)
+    m = first(methods(getfield(mod, :eval)))
+    @test definition(String, m) === nothing
 end
 
 @testset "With Revise" begin