chore: revert changes to instruction_deduplication test

compiler/noirc_evaluator/src/ssa/opt/constant_folding.rs

@@ -187,7 +187,7 @@ mod test {
             instruction::{BinaryOp, Instruction, TerminatorInstruction},
             map::Id,
             types::Type,
-            value::{Value, ValueId},
+            value::Value,
         },
     };
 
@@ -293,24 +293,22 @@ mod test {
     #[test]
     fn instruction_deduplication() {
         // fn main f0 {
-        //   b0(v0: Field):
-        //     v1 = truncate v0 to 32 bits, max_bit_size: 254
-        //     v2 = cast v1 as u32
-        //     v3 = truncate v0 to 32 bits, max_bit_size: 254
-        //     v4 = cast v3 as u32
-        //     constrain v2 v4
+        //   b0(v0: u16):
+        //     v1 = cast v0 as u32
+        //     v2 = cast v0 as u32
+        //     constrain v1 v2
         // }
         //
-        // After constructing this IR, we run constant folding which should replace the second truncation and cast
+        // After constructing this IR, we run constant folding which should replace the second cast
         // with a reference to the results to the first. This then allows us to optimize away
         // the constrain instruction as both inputs are known to be equal.
         //
-        // The first truncation and cast instructions are retained and will be removed in the dead instruction elimination pass.
+        // The first cast instruction is retained and will be removed in the dead instruction elimination pass.
         let main_id = Id::test_new(0);
 
         // Compiling main
         let mut builder = FunctionBuilder::new("main".into(), main_id, RuntimeType::Acir);
-        let v0 = builder.add_parameter(Type::field());
+        let v0 = builder.add_parameter(Type::unsigned(16));
 
         let v1 = builder.insert_cast(v0, Type::unsigned(32));
         let v2 = builder.insert_cast(v0, Type::unsigned(32));
@@ -325,22 +323,15 @@ mod test {
         //
         // fn main f0 {
         //   b0(v0: Field):
-        //     v1 = truncate v0 to 32 bits, max_bit_size: 254
-        //     v2 = cast v1 as u32
+        //     v1 = cast v1 as u32
         // }
         let ssa = ssa.fold_constants();
         let main = ssa.main();
         let instructions = main.dfg[main.entry_block()].instructions();
 
-        assert_eq!(instructions.len(), 2);
+        assert_eq!(instructions.len(), 1);
+        let instruction = &main.dfg[instructions[0]];
 
-        assert_eq!(
-            &main.dfg[instructions[0]],
-            &Instruction::Truncate { value: v0, bit_size: 32, max_bit_size: 254 }
-        );
-        assert_eq!(
-            &main.dfg[instructions[1]],
-            &Instruction::Cast(ValueId::test_new(5), Type::unsigned(32))
-        );
+        assert_eq!(instruction, &Instruction::Cast(v0, Type::unsigned(32)));
     }
 }