assert debugging

JuliaLang · Dec 8, 2017 · 765d6eb · 765d6eb
1 parent 55d854a
commit 765d6eb
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Showing 4 changed files with 16 additions and 8 deletions.
diff --git a/base/strings/io.jl b/base/strings/io.jl
@@ -139,8 +139,10 @@ print(io::IO, s::AbstractString) = (write(io, s); nothing)
 write(io::IO, s::AbstractString) = (len = 0; for c in s; len += write(io, c); end; len)
 show(io::IO, s::AbstractString) = print_quoted(io, s)
 
-write(to::GenericIOBuffer, s::SubString{String}) =
- s.ncodeunits ≤ 0 ? 0 : unsafe_write(to, pointer(s.string, s.offset + 1), UInt(s.ncodeunits))
+function write(to::GenericIOBuffer, s::SubString{String})
+ assert(s.ncodeunits ≥ 0)
+ s.ncodeunits ≤ 0 ? 0 : unsafe_write(to, pointer(s.string, s.offset+1), UInt(s.ncodeunits))
+end
 
 ## printing literal quoted string data ##
 

diff --git a/base/strings/string.jl b/base/strings/string.jl
@@ -82,6 +82,7 @@ end
 
 function ==(a::String, b::String)
  al = sizeof(a)
+ assert(al ≥ 0)
  al == sizeof(b) && 0 == ccall(:memcmp, Int32, (Ptr{UInt8}, Ptr{UInt8}, UInt), a, b, al)
 end
 

diff --git a/base/strings/substring.jl b/base/strings/substring.jl
@@ -86,9 +86,10 @@ prevind(s::SubString, i::Integer) = prevind(s.string, s.offset + i) - s.offset
 function cmp(a::SubString{String}, b::SubString{String})
  na = sizeof(a)
  nb = sizeof(b)
+ assert(na ≥ 0 && nb ≥ 0)
  c = ccall(:memcmp, Int32, (Ptr{UInt8}, Ptr{UInt8}, UInt),
- pointer(a), pointer(b), min(na,nb))
- return c < 0 ? -1 : c > 0 ? +1 : cmp(na,nb)
+ pointer(a), pointer(b), min(na, nb))
+ return c < 0 ? -1 : c > 0 ? +1 : cmp(na, nb)
 end
 
 # don't make unnecessary copies when passing substrings to C functions

diff --git a/base/strings/util.jl b/base/strings/util.jl
@@ -58,10 +58,14 @@ function endswith(a::AbstractString, b::AbstractString)
 end
 endswith(str::AbstractString, chars::Chars) = !isempty(str) && last(str) in chars
 
-startswith(a::String, b::String) =
- (sizeof(a) >= sizeof(b) && ccall(:memcmp, Int32, (Ptr{UInt8}, Ptr{UInt8}, UInt), a, b, sizeof(b)) == 0)
-startswith(a::Vector{UInt8}, b::Vector{UInt8}) =
- (length(a) >= length(b) && ccall(:memcmp, Int32, (Ptr{UInt8}, Ptr{UInt8}, UInt), a, b, length(b)) == 0)
+# FIXME: check that end of `b` doesn't match a partial character in `a`
+function startswith(a::String, b::String)
+ assert(sizeof(b) ≥ 0)
+ sizeof(a) ≥ sizeof(b) &&
+ ccall(:memcmp, Int32, (Ptr{UInt8}, Ptr{UInt8}, UInt), a, b, sizeof(b)) == 0
+end
+startswith(a::Vector{UInt8}, b::Vector{UInt8}) = length(a) ≥ length(b) &&
+ ccall(:memcmp, Int32, (Ptr{UInt8}, Ptr{UInt8}, UInt), a, b, length(b)) == 0
 
 # TODO: fast endswith