diff --git a/ql/test/library-tests/ast/Ast.expected b/ql/test/library-tests/ast/Ast.expected
index 7f5e877af1c..ff9b6cb5dae 100644
--- a/ql/test/library-tests/ast/Ast.expected
+++ b/ql/test/library-tests/ast/Ast.expected
@@ -567,6 +567,21 @@ calls/calls.rb:
 #  319|         getReceiver: [Self] self
 #  319|       getArgument: [IntegerLiteral] 0
 #  319|     getAnOperand/getRightOperand: [IntegerLiteral] 1
+#  320|   getStmt: [AssignMulExpr] ... *= ...
+#  320|     getAnOperand/getLeftOperand: [ElementReference, SetterMethodCall] ...[...]
+#  320|       getReceiver: [MethodCall] call to bar
+#  320|         getReceiver: [MethodCall] call to foo
+#  320|           getReceiver: [Self] self
+#  320|       getArgument: [IntegerLiteral] 0
+#  320|       getArgument: [MethodCall] call to baz
+#  320|         getReceiver: [MethodCall] call to foo
+#  320|           getReceiver: [Self] self
+#  320|       getArgument: [AddExpr] ... + ...
+#  320|         getAnOperand/getLeftOperand: [MethodCall] call to boo
+#  320|           getReceiver: [MethodCall] call to foo
+#  320|             getReceiver: [Self] self
+#  320|         getAnOperand/getRightOperand: [IntegerLiteral] 1
+#  320|     getAnOperand/getRightOperand: [IntegerLiteral] 2
 control/cases.rb:
 #    1| [Toplevel] cases.rb
 #    2|   getStmt: [AssignExpr] ... = ...
@@ -1718,6 +1733,25 @@ operations/operations.rb:
 #   84|   getStmt: [AssignBitwiseXorExpr] ... ^= ...
 #   84|     getAnOperand/getLeftOperand: [LocalVariableAccess] baz
 #   84|     getAnOperand/getRightOperand: [LocalVariableAccess] qux
+#   86|   getStmt: [ClassDeclaration] X
+#   87|     getStmt: [AssignExpr] ... = ...
+#   87|       getAnOperand/getLeftOperand: [InstanceVariableAccess] @x
+#   87|       getAnOperand/getRightOperand: [IntegerLiteral] 1
+#   88|     getStmt: [AssignAddExpr] ... += ...
+#   88|       getAnOperand/getLeftOperand: [InstanceVariableAccess] @x
+#   88|       getAnOperand/getRightOperand: [IntegerLiteral] 2
+#   90|     getStmt: [AssignExpr] ... = ...
+#   90|       getAnOperand/getLeftOperand: [ClassVariableAccess] @@y
+#   90|       getAnOperand/getRightOperand: [IntegerLiteral] 3
+#   91|     getStmt: [AssignDivExpr] ... /= ...
+#   91|       getAnOperand/getLeftOperand: [ClassVariableAccess] @@y
+#   91|       getAnOperand/getRightOperand: [IntegerLiteral] 4
+#   94|   getStmt: [AssignExpr] ... = ...
+#   94|     getAnOperand/getLeftOperand: [GlobalVariableAccess] $global_var
+#   94|     getAnOperand/getRightOperand: [IntegerLiteral] 5
+#   95|   getStmt: [AssignMulExpr] ... *= ...
+#   95|     getAnOperand/getLeftOperand: [GlobalVariableAccess] $global_var
+#   95|     getAnOperand/getRightOperand: [IntegerLiteral] 6
 params/params.rb:
 #    1| [Toplevel] params.rb
 #    4|   getStmt: [Method] identifier_method_params
diff --git a/ql/test/library-tests/ast/calls/calls.expected b/ql/test/library-tests/ast/calls/calls.expected
index 74bcfee07ed..e10de4ae3d5 100644
--- a/ql/test/library-tests/ast/calls/calls.expected
+++ b/ql/test/library-tests/ast/calls/calls.expected
@@ -36,6 +36,12 @@ callsWithArguments
 | calls.rb:317:5:317:10 | ...[...] | []= | 0 | calls.rb:317:9:317:9 | 5 |
 | calls.rb:319:1:319:6 | ...[...] | [] | 0 | calls.rb:319:5:319:5 | 0 |
 | calls.rb:319:1:319:6 | ...[...] | []= | 0 | calls.rb:319:5:319:5 | 0 |
+| calls.rb:320:1:320:32 | ...[...] | [] | 0 | calls.rb:320:9:320:9 | 0 |
+| calls.rb:320:1:320:32 | ...[...] | [] | 1 | calls.rb:320:12:320:18 | call to baz |
+| calls.rb:320:1:320:32 | ...[...] | [] | 2 | calls.rb:320:21:320:31 | ... + ... |
+| calls.rb:320:1:320:32 | ...[...] | []= | 0 | calls.rb:320:9:320:9 | 0 |
+| calls.rb:320:1:320:32 | ...[...] | []= | 1 | calls.rb:320:12:320:18 | call to baz |
+| calls.rb:320:1:320:32 | ...[...] | []= | 2 | calls.rb:320:21:320:31 | ... + ... |
 callsWithReceiver
 | calls.rb:2:1:2:5 | call to foo | calls.rb:2:1:2:5 | self |
 | calls.rb:5:1:5:10 | call to bar | calls.rb:5:1:5:3 | Foo |
@@ -216,6 +222,13 @@ callsWithReceiver
 | calls.rb:318:1:318:10 | call to count/count= | calls.rb:318:1:318:4 | self |
 | calls.rb:319:1:319:3 | call to foo | calls.rb:319:1:319:3 | self |
 | calls.rb:319:1:319:6 | ...[...] | calls.rb:319:1:319:3 | call to foo |
+| calls.rb:320:1:320:3 | call to foo | calls.rb:320:1:320:3 | self |
+| calls.rb:320:1:320:7 | call to bar | calls.rb:320:1:320:3 | call to foo |
+| calls.rb:320:1:320:32 | ...[...] | calls.rb:320:1:320:7 | call to bar |
+| calls.rb:320:12:320:14 | call to foo | calls.rb:320:12:320:14 | self |
+| calls.rb:320:12:320:18 | call to baz | calls.rb:320:12:320:14 | call to foo |
+| calls.rb:320:21:320:23 | call to foo | calls.rb:320:21:320:23 | self |
+| calls.rb:320:21:320:27 | call to boo | calls.rb:320:21:320:23 | call to foo |
 callsWithBlock
 | calls.rb:17:1:17:17 | call to foo | calls.rb:17:5:17:17 | { ... } |
 | calls.rb:20:1:22:3 | call to foo | calls.rb:20:5:22:3 | do ... end |
@@ -262,3 +275,4 @@ setterCalls
 | calls.rb:317:5:317:10 | ...[...] |
 | calls.rb:318:1:318:10 | call to count/count= |
 | calls.rb:319:1:319:6 | ...[...] |
+| calls.rb:320:1:320:32 | ...[...] |
diff --git a/ql/test/library-tests/ast/calls/calls.rb b/ql/test/library-tests/ast/calls/calls.rb
index 8b827d07f9b..1362b043e8a 100644
--- a/ql/test/library-tests/ast/calls/calls.rb
+++ b/ql/test/library-tests/ast/calls/calls.rb
@@ -317,3 +317,4 @@ self.foo, *self.bar, foo[4] = [1, 2, 3, 4]
 a, *foo[5] = [1, 2, 3]
 self.count += 1
 foo[0] += 1
+foo.bar[0, foo.baz, foo.boo + 1] *= 2
diff --git a/ql/test/library-tests/ast/operations/assignment.expected b/ql/test/library-tests/ast/operations/assignment.expected
index d1f34896b31..454f86743ba 100644
--- a/ql/test/library-tests/ast/operations/assignment.expected
+++ b/ql/test/library-tests/ast/operations/assignment.expected
@@ -30,6 +30,12 @@ assignments
 | operations.rb:82:2:82:12 | ... &= ... | &= | operations.rb:82:2:82:4 | foo | operations.rb:82:9:82:12 | mask | AssignBitwiseAndExpr |
 | operations.rb:83:2:83:12 | ... \|= ... | \|= | operations.rb:83:2:83:4 | bar | operations.rb:83:9:83:12 | 0x01 | AssignBitwiseOrExpr |
 | operations.rb:84:2:84:11 | ... ^= ... | ^= | operations.rb:84:2:84:4 | baz | operations.rb:84:9:84:11 | qux | AssignBitwiseXorExpr |
+| operations.rb:87:3:87:8 | ... = ... | = | operations.rb:87:3:87:4 | @x | operations.rb:87:8:87:8 | 1 | AssignExpr |
+| operations.rb:88:3:88:9 | ... += ... | += | operations.rb:88:3:88:4 | @x | operations.rb:88:9:88:9 | 2 | AssignAddExpr |
+| operations.rb:90:3:90:9 | ... = ... | = | operations.rb:90:3:90:5 | @@y | operations.rb:90:9:90:9 | 3 | AssignExpr |
+| operations.rb:91:3:91:10 | ... /= ... | /= | operations.rb:91:3:91:5 | @@y | operations.rb:91:10:91:10 | 4 | AssignDivExpr |
+| operations.rb:94:1:94:15 | ... = ... | = | operations.rb:94:1:94:11 | $global_var | operations.rb:94:15:94:15 | 5 | AssignExpr |
+| operations.rb:95:1:95:16 | ... *= ... | *= | operations.rb:95:1:95:11 | $global_var | operations.rb:95:16:95:16 | 6 | AssignMulExpr |
 assignOperations
 | operations.rb:68:1:68:8 | ... += ... | += | operations.rb:68:1:68:1 | x | operations.rb:68:6:68:8 | 128 | AssignAddExpr |
 | operations.rb:69:1:69:7 | ... -= ... | -= | operations.rb:69:1:69:1 | y | operations.rb:69:6:69:7 | 32 | AssignSubExpr |
@@ -44,6 +50,9 @@ assignOperations
 | operations.rb:82:2:82:12 | ... &= ... | &= | operations.rb:82:2:82:4 | foo | operations.rb:82:9:82:12 | mask | AssignBitwiseAndExpr |
 | operations.rb:83:2:83:12 | ... \|= ... | \|= | operations.rb:83:2:83:4 | bar | operations.rb:83:9:83:12 | 0x01 | AssignBitwiseOrExpr |
 | operations.rb:84:2:84:11 | ... ^= ... | ^= | operations.rb:84:2:84:4 | baz | operations.rb:84:9:84:11 | qux | AssignBitwiseXorExpr |
+| operations.rb:88:3:88:9 | ... += ... | += | operations.rb:88:3:88:4 | @x | operations.rb:88:9:88:9 | 2 | AssignAddExpr |
+| operations.rb:91:3:91:10 | ... /= ... | /= | operations.rb:91:3:91:5 | @@y | operations.rb:91:10:91:10 | 4 | AssignDivExpr |
+| operations.rb:95:1:95:16 | ... *= ... | *= | operations.rb:95:1:95:11 | $global_var | operations.rb:95:16:95:16 | 6 | AssignMulExpr |
 assignArithmeticOperations
 | operations.rb:68:1:68:8 | ... += ... | += | operations.rb:68:1:68:1 | x | operations.rb:68:6:68:8 | 128 | AssignAddExpr |
 | operations.rb:69:1:69:7 | ... -= ... | -= | operations.rb:69:1:69:1 | y | operations.rb:69:6:69:7 | 32 | AssignSubExpr |
@@ -51,6 +60,9 @@ assignArithmeticOperations
 | operations.rb:71:1:71:6 | ... /= ... | /= | operations.rb:71:1:71:1 | b | operations.rb:71:6:71:6 | 4 | AssignDivExpr |
 | operations.rb:72:1:72:6 | ... %= ... | %= | operations.rb:72:1:72:1 | z | operations.rb:72:6:72:6 | 2 | AssignModuloExpr |
 | operations.rb:73:1:73:11 | ... **= ... | **= | operations.rb:73:1:73:3 | foo | operations.rb:73:9:73:11 | bar | AssignExponentExpr |
+| operations.rb:88:3:88:9 | ... += ... | += | operations.rb:88:3:88:4 | @x | operations.rb:88:9:88:9 | 2 | AssignAddExpr |
+| operations.rb:91:3:91:10 | ... /= ... | /= | operations.rb:91:3:91:5 | @@y | operations.rb:91:10:91:10 | 4 | AssignDivExpr |
+| operations.rb:95:1:95:16 | ... *= ... | *= | operations.rb:95:1:95:11 | $global_var | operations.rb:95:16:95:16 | 6 | AssignMulExpr |
 assignLogicalOperations
 | operations.rb:76:2:76:8 | ... &&= ... | &&= | operations.rb:76:2:76:2 | x | operations.rb:76:8:76:8 | y | AssignLogicalAndExpr |
 | operations.rb:77:2:77:8 | ... \|\|= ... | \|\|= | operations.rb:77:2:77:2 | a | operations.rb:77:8:77:8 | b | AssignLogicalOrExpr |
diff --git a/ql/test/library-tests/ast/operations/operation.expected b/ql/test/library-tests/ast/operations/operation.expected
index 3d5346e6346..7f4d25068eb 100644
--- a/ql/test/library-tests/ast/operations/operation.expected
+++ b/ql/test/library-tests/ast/operations/operation.expected
@@ -116,3 +116,15 @@
 | operations.rb:83:2:83:12 | ... \|= ... | \|= | operations.rb:83:9:83:12 | 0x01 | AssignBitwiseOrExpr |
 | operations.rb:84:2:84:11 | ... ^= ... | ^= | operations.rb:84:2:84:4 | baz | AssignBitwiseXorExpr |
 | operations.rb:84:2:84:11 | ... ^= ... | ^= | operations.rb:84:9:84:11 | qux | AssignBitwiseXorExpr |
+| operations.rb:87:3:87:8 | ... = ... | = | operations.rb:87:3:87:4 | @x | AssignExpr |
+| operations.rb:87:3:87:8 | ... = ... | = | operations.rb:87:8:87:8 | 1 | AssignExpr |
+| operations.rb:88:3:88:9 | ... += ... | += | operations.rb:88:3:88:4 | @x | AssignAddExpr |
+| operations.rb:88:3:88:9 | ... += ... | += | operations.rb:88:9:88:9 | 2 | AssignAddExpr |
+| operations.rb:90:3:90:9 | ... = ... | = | operations.rb:90:3:90:5 | @@y | AssignExpr |
+| operations.rb:90:3:90:9 | ... = ... | = | operations.rb:90:9:90:9 | 3 | AssignExpr |
+| operations.rb:91:3:91:10 | ... /= ... | /= | operations.rb:91:3:91:5 | @@y | AssignDivExpr |
+| operations.rb:91:3:91:10 | ... /= ... | /= | operations.rb:91:10:91:10 | 4 | AssignDivExpr |
+| operations.rb:94:1:94:15 | ... = ... | = | operations.rb:94:1:94:11 | $global_var | AssignExpr |
+| operations.rb:94:1:94:15 | ... = ... | = | operations.rb:94:15:94:15 | 5 | AssignExpr |
+| operations.rb:95:1:95:16 | ... *= ... | *= | operations.rb:95:1:95:11 | $global_var | AssignMulExpr |
+| operations.rb:95:1:95:16 | ... *= ... | *= | operations.rb:95:16:95:16 | 6 | AssignMulExpr |
diff --git a/ql/test/library-tests/ast/operations/operations.rb b/ql/test/library-tests/ast/operations/operations.rb
index 707a2d36425..effee5860ba 100644
--- a/ql/test/library-tests/ast/operations/operations.rb
+++ b/ql/test/library-tests/ast/operations/operations.rb
@@ -81,4 +81,15 @@ foo **= bar
  y >>= 3
  foo &= mask
  bar |= 0x01
- baz ^= qux
\ No newline at end of file
+ baz ^= qux
+
+class X
+  @x = 1
+  @x += 2
+
+  @@y = 3
+  @@y /= 4
+end
+
+$global_var = 5
+$global_var *= 6
diff --git a/ql/test/library-tests/controlflow/graph/Cfg.expected b/ql/test/library-tests/controlflow/graph/Cfg.expected
index 3e39856c559..84e66808854 100644
--- a/ql/test/library-tests/controlflow/graph/Cfg.expected
+++ b/ql/test/library-tests/controlflow/graph/Cfg.expected
@@ -2083,6 +2083,177 @@ cfg.rb:
 #  194| x
 #-----|  -> call to puts
 
+desugar.rb:
+#    1| enter m1
+#-----|  -> x
+
+#    1| enter desugar.rb
+#-----|  -> m1
+
+#    1| m1
+#-----|  -> m2
+
+#    1| exit m1
+
+#    1| exit desugar.rb
+
+#    1| exit m1 (normal)
+#-----|  -> exit m1
+
+#    1| exit desugar.rb (normal)
+#-----|  -> exit desugar.rb
+
+#    1| x
+#-----|  -> x
+
+#    2| ... += ...
+#-----|  -> exit m1 (normal)
+
+#    2| x
+#-----|  -> 1
+
+#    2| 1
+#-----|  -> ... += ...
+
+#    5| enter m2
+#-----|  -> x
+
+#    5| m2
+#-----|  -> m3
+
+#    5| exit m2
+
+#    5| exit m2 (normal)
+#-----|  -> exit m2
+
+#    5| x
+#-----|  -> x
+
+#    6| ... += ...
+#-----|  -> exit m2 (normal)
+
+#    6| call to count/count=
+#-----|  -> 1
+
+#    6| call to foo
+#-----|  -> call to count/count=
+
+#    6| x
+#-----|  -> call to foo
+
+#    6| 1
+#-----|  -> ... += ...
+
+#    9| enter m3
+#-----|  -> x
+
+#    9| m3
+#-----|  -> X
+
+#    9| exit m3
+
+#    9| exit m3 (normal)
+#-----|  -> exit m3
+
+#    9| x
+#-----|  -> y
+
+#    9| y
+#-----|  -> x
+
+#   10| ... += ...
+#-----|  -> exit m3 (normal)
+
+#   10| ...[...]
+#-----|  -> 1
+
+#   10| call to foo
+#-----|  -> 0
+
+#   10| x
+#-----|  -> call to foo
+
+#   10| 0
+#-----|  -> y
+
+#   10| call to bar
+#-----|  -> x
+
+#   10| y
+#-----|  -> call to bar
+
+#   10| ... + ...
+#-----|  -> ...[...]
+
+#   10| call to baz
+#-----|  -> 3
+
+#   10| x
+#-----|  -> call to baz
+
+#   10| 3
+#-----|  -> ... + ...
+
+#   10| 1
+#-----|  -> ... += ...
+
+#   13| X
+#-----|  -> @x
+
+#   14| ... = ...
+#-----|  -> @x
+
+#   14| @x
+#-----|  -> 1
+
+#   14| 1
+#-----|  -> ... = ...
+
+#   15| ... += ...
+#-----|  -> @@y
+
+#   15| @x
+#-----|  -> 2
+
+#   15| 2
+#-----|  -> ... += ...
+
+#   17| ... = ...
+#-----|  -> @@y
+
+#   17| @@y
+#-----|  -> 3
+
+#   17| 3
+#-----|  -> ... = ...
+
+#   18| ... /= ...
+#-----|  -> $global_var
+
+#   18| @@y
+#-----|  -> 4
+
+#   18| 4
+#-----|  -> ... /= ...
+
+#   21| ... = ...
+#-----|  -> $global_var
+
+#   21| $global_var
+#-----|  -> 5
+
+#   21| 5
+#-----|  -> ... = ...
+
+#   22| ... *= ...
+#-----|  -> exit desugar.rb (normal)
+
+#   22| $global_var
+#-----|  -> 6
+
+#   22| 6
+#-----|  -> ... *= ...
+
 exit.rb:
 #    1| enter m1
 #-----|  -> x
diff --git a/ql/test/library-tests/controlflow/graph/desugar.rb b/ql/test/library-tests/controlflow/graph/desugar.rb
new file mode 100644
index 00000000000..25dd0e48e0e
--- /dev/null
+++ b/ql/test/library-tests/controlflow/graph/desugar.rb
@@ -0,0 +1,22 @@
+def m1 x
+  x += 1
+end
+
+def m2 x
+  x.foo.count += 1
+end
+
+def m3 x, y
+  x.foo[0, y.bar, x.baz + 3] += 1
+end
+
+class X
+  @x = 1
+  @x += 2
+
+  @@y = 3
+  @@y /= 4
+end
+
+$global_var = 5
+$global_var *= 6