Improve handling of duplicate slotnames

src/breakpoints.jl

@@ -189,19 +189,18 @@ end
 
 function prepare_slotfunction(framecode::FrameCode, body::Union{Symbol,Expr})
     uslotnames = Set{Symbol}()
-    slotnames  = Symbol[]
-    for name in framecode.src.slotnames
-        if name ∉ uslotnames
-            push!(slotnames, name)
-            push!(uslotnames, name)
-        end
-    end
     framename, dataname = gensym("frame"), gensym("data")
     assignments = Expr[:($dataname = $framename.framedata)]
     default = Unassigned()
-    for i = 1:length(slotnames)
-        slotname = framecode.src.slotnames[i]
-        qslotname = QuoteNode(slotname)
+    for slotname in framecode.src.slotnames
+        if slotname === Symbol("")
+            continue
+        end
+        if slotname ∉ uslotnames
+            push!(uslotnames, slotname)
+        else
+            continue
+        end
         list = framecode.slotnamelists[slotname]
         if length(list) == 1
             maxexpr = :($dataname.last_reference[$(list[1])] > 0 ? $(list[1]) : 0)

test/breakpoints.jl

@@ -433,3 +433,25 @@ empty!(breakpoint_update_hooks)
         remove()
     end
 end
+
+@testset "duplicate slotnames" begin
+    tmp_dupl() = (1,2,3,4)
+    ln = @__LINE__
+    function duplnames(x)
+        for iter in Iterators.CartesianIndices(x)
+            i = iter[1]
+            c = i
+            a, b, c, d = tmp_dupl()
+        end
+        return x
+    end
+    bp = breakpoint(@__FILE__, ln+5, :(i == 1))
+    c = @code_lowered(duplnames((1,2)))
+    if length(unique(c.slotnames)) < length(c.slotnames)
+        f = JuliaInterpreter.enter_call(duplnames, (1,2))
+        ex = JuliaInterpreter.prepare_slotfunction(f.framecode, :(i==1))
+        @test ex isa Expr
+        @test ex.args[end].args[end-1].args[1] == :i
+        @test last(JuliaInterpreter.debug_command(f, :c)) isa BreakpointRef
+    end
+end