Tweak C type name sanitizer

This should remove some gnarly-looking underscores.

Author: topolarity

src/c.jl

@@ -106,7 +106,11 @@ const ctypes = Dict{String, String}(
 
 function sanitize_for_c(str::AbstractString)
     # Replace any non alphanumeric characters with '_'
-    return replace(str, r"[^a-zA-Z0-9_]" => "_")
+    str = replace(str, r"[^a-zA-Z0-9_]" => "_")
+    # Strip any leading / trailing underscores
+    str = strip(str, Char['_'])
+    # Merge any repeated underscores to just one
+    return replace(str, r"_+" => "_")
 end
 
 function mangle_c!(typedict::Dict{Int, String}, type_id::Int, typeinfo::OrderedDict{Int,TypeDesc})
@@ -125,6 +129,9 @@ function mangle_c!(typedict::Dict{Int, String}, type_id::Int, typeinfo::OrderedD
     elseif type isa StructDesc
         mangled = sanitize_for_c(type.name)
     end
+    # FIXME: this function should check for name collisions at this stage (which can happen due to
+    #        sanitization or name ambiguity in the printing from Julia) and gensym a unique suffix
+    #        if necessary
     typedict[type_id] = mangled
     return mangled
 end

test/runtests.jl

@@ -85,12 +85,12 @@ end
             @test occursin("#include <stddef.h>", content)
             @test occursin("#include <stdint.h>", content)
             @test occursin("#include <stdbool.h>", content)
-            @test occursin("typedef struct CVector_Float32_ {", content)
+            @test occursin("typedef struct CVector_Float32 {", content)
             @test occursin("    int32_t length;", content)
             @test occursin("    float* data;", content)
-            @test occursin("CVector_Float32_ from;", content)
-            @test occursin("CVector_Float32_ to;", content)
-            @test occursin("float copyto_and_sum(CVectorPair_Float32_ fromto);", content)
+            @test occursin("CVector_Float32 from;", content)
+            @test occursin("CVector_Float32 to;", content)
+            @test occursin("float copyto_and_sum(CVectorPair_Float32 fromto);", content)
             @test occursin("int32_t countsame(MyTwoVec* list, int32_t n);", content)
         end
     end