Merge pull request #183 from JuliaDebug/teh/fix_178

 Ensure slots get assigned in `finish_stack!`

Author: timholy

src/JuliaInterpreter.jl

@@ -59,6 +59,8 @@ function set_compiled_methods()
     push!(compiled_methods, which(reenable_sigint, Tuple{Function}))
     # Signal-handling in the `print` dispatch hierarchy
     push!(compiled_methods, which(Base.unsafe_write, Tuple{Base.LibuvStream, Ptr{UInt8}, UInt}))
+    push!(compiled_methods, which(print, Tuple{IO, Any}))
+    push!(compiled_methods, which(print, Tuple{IO, Any, Any}))
     # Libc.GetLastError()
     @static if Sys.iswindows()
         push!(compiled_methods, which(Base.access_env, Tuple{Function, AbstractString}))

src/commands.jl

@@ -67,6 +67,12 @@ function finish_stack!(@nospecialize(recurse), frame::Frame, rootistoplevel::Boo
         if isassign(frame, pc)
             lhs = getlhs(pc)
             do_assignment!(frame, lhs, ret)
+        else
+            stmt = pc_expr(frame, pc)
+            if isexpr(stmt, :(=))
+                lhs = stmt.args[1]
+                do_assignment!(frame, lhs, ret)
+            end
         end
         pc += 1
         frame.pc = pc

src/construct.jl

@@ -643,6 +643,9 @@ macro interpret(arg)
             frame, BreakpointRef(frame.framecode, 1)
         else
             local ret = finish_and_return!(frame)
+            # We deliberately return the top frame here; future debugging commands
+            # via debug_command may alter the leaves, we want the top frame so we can
+            # ultimately do `get_return`.
             isa(ret, BreakpointRef) ? (frame, ret) : ret
         end
     end

test/debug.jl

@@ -329,4 +329,13 @@ struct B{T} end
             @test get_return(fr) == 2
         end
     end
+
+    @testset "Issue #178" begin
+        remove()
+        a = [1, 2, 3, 4]
+        @breakpoint length(LinearIndices(a))
+        frame, bp = @interpret sum(a)
+        @test debug_command(frame, :c) === nothing
+        @test get_return(frame) == sum(a)
+    end
 # end