feat: add --broadcast flag to forge create, default to dry run mode (foundry-rs#9420)

* add --broadcast flag to forge create, default to dry run

* nits

* fix tests

* add dry run tests incl --json

* minor fixes, failing test due to minor bytecode difference

Author: zerosnacks

crates/forge/bin/cmd/create.rs

@@ -61,6 +61,10 @@ pub struct CreateArgs {
     )]
     constructor_args_path: Option<PathBuf>,
 
+    /// Broadcast the transaction.
+    #[arg(long)]
+    pub broadcast: bool,
+
     /// Verify contract after creation.
     #[arg(long)]
     verify: bool,
@@ -155,6 +159,10 @@ impl CreateArgs {
         } else {
             provider.get_chain_id().await?
         };
+
+        // Whether to broadcast the transaction or not
+        let dry_run = !self.broadcast;
+
         if self.unlocked {
             // Deploy with unlocked account
             let sender = self.eth.wallet.from.expect("required");
@@ -167,6 +175,7 @@ impl CreateArgs {
                 sender,
                 config.transaction_timeout,
                 id,
+                dry_run,
             )
             .await
         } else {
@@ -185,6 +194,7 @@ impl CreateArgs {
                 deployer,
                 config.transaction_timeout,
                 id,
+                dry_run,
             )
             .await
         }
@@ -260,6 +270,7 @@ impl CreateArgs {
         deployer_address: Address,
         timeout: u64,
         id: ArtifactId,
+        dry_run: bool,
     ) -> Result<()> {
         let bin = bin.into_bytes().unwrap_or_else(|| {
             panic!("no bytecode found in bin object for {}", self.contract.name)
@@ -339,6 +350,30 @@ impl CreateArgs {
             self.verify_preflight_check(constructor_args.clone(), chain, &id).await?;
         }
 
+        if dry_run {
+            if !shell::is_json() {
+                sh_warn!("Dry run enabled, not broadcasting transaction\n")?;
+
+                sh_println!("Contract: {}", self.contract.name)?;
+                sh_println!(
+                    "Transaction: {}",
+                    serde_json::to_string_pretty(&deployer.tx.clone())?
+                )?;
+                sh_println!("ABI: {}\n", serde_json::to_string_pretty(&abi)?)?;
+
+                sh_warn!("To broadcast this transaction, add --broadcast to the previous command. See forge create --help for more.")?;
+            } else {
+                let output = json!({
+                    "contract": self.contract.name,
+                    "transaction": &deployer.tx,
+                    "abi":&abi
+                });
+                sh_println!("{}", serde_json::to_string_pretty(&output)?)?;
+            }
+
+            return Ok(());
+        }
+
         // Deploy the actual contract
         let (deployed_contract, receipt) = deployer.send_with_receipt().await?;
 
@@ -349,7 +384,7 @@ impl CreateArgs {
                 "deployedTo": address.to_string(),
                 "transactionHash": receipt.transaction_hash
             });
-            sh_println!("{output}")?;
+            sh_println!("{}", serde_json::to_string_pretty(&output)?)?;
         } else {
             sh_println!("Deployer: {deployer_address}")?;
             sh_println!("Deployed to: {address}")?;

crates/forge/tests/cli/create.rs

@@ -9,7 +9,9 @@ use anvil::{spawn, NodeConfig};
 use foundry_compilers::artifacts::{remappings::Remapping, BytecodeHash};
 use foundry_config::Config;
 use foundry_test_utils::{
-    forgetest, forgetest_async, str,
+    forgetest, forgetest_async,
+    snapbox::IntoData,
+    str,
     util::{OutputExt, TestCommand, TestProject},
 };
 use std::str::FromStr;
@@ -145,6 +147,7 @@ forgetest_async!(can_create_template_contract, |prj, cmd| {
     let config = Config { bytecode_hash: BytecodeHash::None, ..Default::default() };
     prj.write_config(config);
 
+    // Dry-run without the `--broadcast` flag
     cmd.forge_fuse().args([
         "create",
         format!("./src/{TEMPLATE_CONTRACT}.sol:{TEMPLATE_CONTRACT}").as_str(),
@@ -154,20 +157,131 @@ forgetest_async!(can_create_template_contract, |prj, cmd| {
         pk.as_str(),
     ]);
 
+    // Dry-run
     cmd.assert().stdout_eq(str![[r#"
 [COMPILING_FILES] with [SOLC_VERSION]
 [SOLC_VERSION] [ELAPSED]
 Compiler run successful!
-Deployer: 0xf39Fd6e51aad88F6F4ce6aB8827279cffFb92266
-Deployed to: 0x5FbDB2315678afecb367f032d93F642f64180aa3
-[TX_HASH]
+Contract: Counter
+Transaction: {
+  "from": "0xf39fd6e51aad88f6f4ce6ab8827279cfffb92266",
+  "to": null,
+  "maxFeePerGas": "0x77359401",
+  "maxPriorityFeePerGas": "0x1",
+  "gas": "0x17575",
+  "input": "[..]",
+  "nonce": "0x0",
+  "chainId": "0x7a69"
+}
+ABI: [
+  {
+    "type": "function",
+    "name": "increment",
+    "inputs": [],
+    "outputs": [],
+    "stateMutability": "nonpayable"
+  },
+  {
+    "type": "function",
+    "name": "number",
+    "inputs": [],
+    "outputs": [
+      {
+        "name": "",
+        "type": "uint256",
+        "internalType": "uint256"
+      }
+    ],
+    "stateMutability": "view"
+  },
+  {
+    "type": "function",
+    "name": "setNumber",
+    "inputs": [
+      {
+        "name": "newNumber",
+        "type": "uint256",
+        "internalType": "uint256"
+      }
+    ],
+    "outputs": [],
+    "stateMutability": "nonpayable"
+  }
+]
+
 
 "#]]);
 
+    // Dry-run with `--json` flag
+    cmd.arg("--json").assert().stdout_eq(
+        str![[r#"
+{
+  "contract": "Counter",
+  "transaction": {
+    "from": "0xf39fd6e51aad88f6f4ce6ab8827279cfffb92266",
+    "to": null,
+    "maxFeePerGas": "0x77359401",
+    "maxPriorityFeePerGas": "0x1",
+    "gas": "0x17575",
+    "input": "[..]",
+    "nonce": "0x0",
+    "chainId": "0x7a69"
+  },
+  "abi": [
+    {
+      "type": "function",
+      "name": "increment",
+      "inputs": [],
+      "outputs": [],
+      "stateMutability": "nonpayable"
+    },
+    {
+      "type": "function",
+      "name": "number",
+      "inputs": [],
+      "outputs": [
+        {
+          "name": "",
+          "type": "uint256",
+          "internalType": "uint256"
+        }
+      ],
+      "stateMutability": "view"
+    },
+    {
+      "type": "function",
+      "name": "setNumber",
+      "inputs": [
+        {
+          "name": "newNumber",
+          "type": "uint256",
+          "internalType": "uint256"
+        }
+      ],
+      "outputs": [],
+      "stateMutability": "nonpayable"
+    }
+  ]
+}
+
+"#]]
+        .is_json(),
+    );
+
+    cmd.forge_fuse().args([
+        "create",
+        format!("./src/{TEMPLATE_CONTRACT}.sol:{TEMPLATE_CONTRACT}").as_str(),
+        "--rpc-url",
+        rpc.as_str(),
+        "--private-key",
+        pk.as_str(),
+        "--broadcast",
+    ]);
+
     cmd.assert().stdout_eq(str![[r#"
 No files changed, compilation skipped
 Deployer: 0xf39Fd6e51aad88F6F4ce6aB8827279cffFb92266
-Deployed to: 0xe7f1725E7734CE288F8367e1Bb143E90bb3F0512
+Deployed to: 0x5FbDB2315678afecb367f032d93F642f64180aa3
 [TX_HASH]
 
 "#]]);
@@ -193,6 +307,7 @@ forgetest_async!(can_create_using_unlocked, |prj, cmd| {
         "--from",
         format!("{dev:?}").as_str(),
         "--unlocked",
+        "--broadcast",
     ]);
 
     cmd.assert().stdout_eq(str![[r#"
@@ -204,6 +319,7 @@ Deployed to: 0x5FbDB2315678afecb367f032d93F642f64180aa3
 [TX_HASH]
 
 "#]]);
+
     cmd.assert().stdout_eq(str![[r#"
 No files changed, compilation skipped
 Deployer: 0xf39Fd6e51aad88F6F4ce6aB8827279cffFb92266
@@ -248,6 +364,7 @@ contract ConstructorContract {
             rpc.as_str(),
             "--private-key",
             pk.as_str(),
+            "--broadcast",
             "--constructor-args",
             "My Constructor",
         ])
@@ -285,6 +402,7 @@ contract TupleArrayConstructorContract {
             rpc.as_str(),
             "--private-key",
             pk.as_str(),
+            "--broadcast",
             "--constructor-args",
             "[(1,2), (2,3), (3,4)]",
         ])
@@ -335,6 +453,7 @@ contract UniswapV2Swap {
             rpc.as_str(),
             "--private-key",
             pk.as_str(),
+            "--broadcast",
         ])
         .assert_success()
         .stdout_eq(str![[r#"