fix(forge): reset gas to original after pauseGasMetering (#8717)

crates/cheatcodes/src/inspector.rs

@@ -1354,7 +1354,13 @@ impl Cheatcodes {
                         // inside it.
                         self.gas_metering_create = Some(None)
                     }
-                    opcode::STOP | opcode::RETURN | opcode::SELFDESTRUCT | opcode::REVERT => {
+                    opcode::STOP => {
+                        // Reset gas to value recorded when paused.
+                        interpreter.gas = *gas;
+                        self.gas_metering = None;
+                        self.gas_metering_create = None;
+                    }
+                    opcode::RETURN | opcode::SELFDESTRUCT | opcode::REVERT => {
                         match &self.gas_metering_create {
                             None | Some(None) => {
                                 // If we are ending current execution frame, we want to reset

crates/forge/tests/cli/test_cmd.rs

@@ -1238,3 +1238,51 @@ contract DeterministicRandomnessTest is Test {
     assert_ne!(res4, res1);
     assert_ne!(res4, res3);
 });
+
+// tests that `pauseGasMetering` used at the end of test does not produce meaningless values
+// see https://github.com/foundry-rs/foundry/issues/5491
+forgetest_init!(repro_5491, |prj, cmd| {
+    prj.wipe_contracts();
+
+    prj.add_test(
+        "ATest.t.sol",
+        r#"
+import {Test} from "forge-std/Test.sol";
+
+contract ATest is Test {
+    function testWeirdGas1() public {
+        vm.pauseGasMetering();
+    }
+
+    function testWeirdGas2() public {
+        uint256 a = 1;
+        uint256 b = a + 1;
+        require(b == 2, "b is not 2");
+        vm.pauseGasMetering();
+    }
+
+    function testNormalGas() public {
+        vm.pauseGasMetering();
+        vm.resumeGasMetering();
+    }
+
+    function testWithAssembly() public {
+        vm.pauseGasMetering();
+        assembly {
+            return(0, 0)
+        }
+    }
+}
+   "#,
+    )
+    .unwrap();
+
+    cmd.args(["test"]).with_no_redact().assert_success().stdout_eq(str![[r#"
+...
+[PASS] testNormalGas() (gas: 3202)
+[PASS] testWeirdGas1() (gas: 3040)
+[PASS] testWeirdGas2() (gas: 3148)
+[PASS] testWithAssembly() (gas: 3083)
+...
+"#]]);
+});

crates/test-utils/src/util.rs

@@ -624,6 +624,7 @@ impl TestProject {
             current_dir_lock: None,
             saved_cwd: pretty_err("<current dir>", std::env::current_dir()),
             stdin_fun: None,
+            redact_output: true,
         }
     }
 
@@ -638,6 +639,7 @@ impl TestProject {
             current_dir_lock: None,
             saved_cwd: pretty_err("<current dir>", std::env::current_dir()),
             stdin_fun: None,
+            redact_output: true,
         }
     }
 
@@ -735,6 +737,8 @@ pub struct TestCommand {
     // initial: Command,
     current_dir_lock: Option<parking_lot::lock_api::MutexGuard<'static, parking_lot::RawMutex, ()>>,
     stdin_fun: Option<Box<dyn FnOnce(ChildStdin)>>,
+    /// If true, command output is redacted.
+    redact_output: bool,
 }
 
 impl TestCommand {
@@ -825,6 +829,12 @@ impl TestCommand {
         self
     }
 
+    /// Does not apply [`snapbox`] redactions to the command output.
+    pub fn with_no_redact(&mut self) -> &mut Self {
+        self.redact_output = false;
+        self
+    }
+
     /// Returns the `Config` as spit out by `forge config`
     #[track_caller]
     pub fn config(&mut self) -> Config {
@@ -1053,7 +1063,11 @@ stderr:
     /// Runs the command, returning a [`snapbox`] object to assert the command output.
     #[track_caller]
     pub fn assert(&mut self) -> OutputAssert {
-        OutputAssert::new(self.execute()).with_assert(test_assert())
+        let assert = OutputAssert::new(self.execute());
+        if self.redact_output {
+            return assert.with_assert(test_assert());
+        };
+        assert
     }
 
     /// Runs the command and asserts that it resulted in success.