From 51117ccbc0e77758118fffbd96c8975c506f6c54 Mon Sep 17 00:00:00 2001
From: Hernando Castano <hernando@hcastano.com>
Date: Wed, 10 Aug 2022 18:00:00 -0400
Subject: [PATCH 01/21] Add skeleton of `Verify` command

---
 crates/cargo-contract/src/cmd/mod.rs    |  2 ++
 crates/cargo-contract/src/cmd/verify.rs | 38 +++++++++++++++++++++++++
 crates/cargo-contract/src/main.rs       |  5 ++++
 3 files changed, 45 insertions(+)
 create mode 100644 crates/cargo-contract/src/cmd/verify.rs

diff --git a/crates/cargo-contract/src/cmd/mod.rs b/crates/cargo-contract/src/cmd/mod.rs
index 31a73208f..c1b2b7302 100644
--- a/crates/cargo-contract/src/cmd/mod.rs
+++ b/crates/cargo-contract/src/cmd/mod.rs
@@ -19,6 +19,7 @@ pub mod decode;
 pub mod metadata;
 pub mod new;
 pub mod test;
+pub mod verify;
 
 pub(crate) use self::{
     build::{
@@ -27,6 +28,7 @@ pub(crate) use self::{
     },
     decode::DecodeCommand,
     test::TestCommand,
+    verify::VerifyCommand,
 };
 mod extrinsics;
 
diff --git a/crates/cargo-contract/src/cmd/verify.rs b/crates/cargo-contract/src/cmd/verify.rs
new file mode 100644
index 000000000..727d3021a
--- /dev/null
+++ b/crates/cargo-contract/src/cmd/verify.rs
@@ -0,0 +1,38 @@
+// Copyright 2018-2022 Parity Technologies (UK) Ltd.
+// This file is part of cargo-contract.
+//
+// cargo-contract is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// cargo-contract is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with cargo-contract.  If not, see <http://www.gnu.org/licenses/>.
+
+use crate::workspace::ManifestPath;
+
+use anyhow::Result;
+
+use std::path::PathBuf;
+
+#[derive(Debug, clap::Args)]
+#[clap(name = "verify")]
+pub struct VerifyCommand {
+    /// Path to the `Cargo.toml` of the contract to verify.
+    #[clap(long, parse(from_os_str))]
+    manifest_path: Option<PathBuf>,
+    /// The reference Wasm contract (`*.contract`) that the workspace will be checked against.
+    contract_wasm: String,
+}
+
+impl VerifyCommand {
+    pub fn run(&self) -> Result<()> {
+        let manifest_path = ManifestPath::try_from(self.manifest_path.as_ref())?;
+        todo!()
+    }
+}
diff --git a/crates/cargo-contract/src/main.rs b/crates/cargo-contract/src/main.rs
index afdbf2363..6d5806c1f 100644
--- a/crates/cargo-contract/src/main.rs
+++ b/crates/cargo-contract/src/main.rs
@@ -34,6 +34,7 @@ use self::{
         InstantiateCommand,
         TestCommand,
         UploadCommand,
+        VerifyCommand,
     },
     util::DEFAULT_KEY_COL_WIDTH,
     workspace::ManifestPath,
@@ -504,6 +505,9 @@ enum Command {
     /// Decodes a contracts input or output data (supplied in hex-encoding)
     #[clap(name = "decode")]
     Decode(DecodeCommand),
+    /// Verifies that a given contract binary matches the build result of the specified workspace.
+    #[clap(name = "verify")]
+    Verify(VerifyCommand),
 }
 
 fn main() {
@@ -570,6 +574,7 @@ fn exec(cmd: Command) -> Result<()> {
                 .map_err(|err| map_extrinsic_err(err, call.is_json()))
         }
         Command::Decode(decode) => decode.run().map_err(format_err),
+        Command::Verify(verify) => verify.run(),
     }
 }
 

From 13d29dc912861acf7d42ce472dfc9d6eb250fa95 Mon Sep 17 00:00:00 2001
From: Hernando Castano <hernando@hcastano.com>
Date: Wed, 10 Aug 2022 18:26:48 -0400
Subject: [PATCH 02/21] Read `BuildInfo` from contract metadata

---
 crates/cargo-contract/src/cmd/verify.rs | 31 +++++++++++++++++++++----
 1 file changed, 27 insertions(+), 4 deletions(-)

diff --git a/crates/cargo-contract/src/cmd/verify.rs b/crates/cargo-contract/src/cmd/verify.rs
index 727d3021a..7545e18a6 100644
--- a/crates/cargo-contract/src/cmd/verify.rs
+++ b/crates/cargo-contract/src/cmd/verify.rs
@@ -14,11 +14,19 @@
 // You should have received a copy of the GNU General Public License
 // along with cargo-contract.  If not, see <http://www.gnu.org/licenses/>.
 
-use crate::workspace::ManifestPath;
+use crate::{
+    cmd::metadata::BuildInfo,
+    workspace::ManifestPath,
+};
 
 use anyhow::Result;
+use contract_metadata::ContractMetadata;
 
-use std::path::PathBuf;
+use std::{
+    fs::File,
+    io::prelude::Read,
+    path::PathBuf,
+};
 
 #[derive(Debug, clap::Args)]
 #[clap(name = "verify")]
@@ -27,12 +35,27 @@ pub struct VerifyCommand {
     #[clap(long, parse(from_os_str))]
     manifest_path: Option<PathBuf>,
     /// The reference Wasm contract (`*.contract`) that the workspace will be checked against.
-    contract_wasm: String,
+    contract: PathBuf,
 }
 
 impl VerifyCommand {
     pub fn run(&self) -> Result<()> {
-        let manifest_path = ManifestPath::try_from(self.manifest_path.as_ref())?;
+        let _manifest_path = ManifestPath::try_from(self.manifest_path.as_ref())?;
+
+        // 1. Read the given metadata, and pull out the `BuildInfo`
+        let mut file = File::open(&self.contract)?;
+        let mut contents = String::new();
+        file.read_to_string(&mut contents)?;
+
+        let metadata: ContractMetadata = serde_json::from_str(&contents)?;
+        let build_info = metadata.source.build_info.as_ref().unwrap();
+        let build_info: BuildInfo =
+            serde_json::from_value(build_info.clone().into()).unwrap();
+        dbg!(&build_info);
+
+        // 2. Call `cmd::Build` with the given `BuildInfo`
+        //
+        // 3. Read output file, compare with given contract_wasm
         todo!()
     }
 }

From 85ccd7dd282ac01d5a075f8055fbc2bd4bb076fc Mon Sep 17 00:00:00 2001
From: Hernando Castano <hernando@hcastano.com>
Date: Wed, 10 Aug 2022 18:39:10 -0400
Subject: [PATCH 03/21] Manually build contract using `BuildInfo`

---
 crates/cargo-contract/src/cmd/verify.rs | 27 ++++++++++++++++++++++---
 1 file changed, 24 insertions(+), 3 deletions(-)

diff --git a/crates/cargo-contract/src/cmd/verify.rs b/crates/cargo-contract/src/cmd/verify.rs
index 7545e18a6..b87ac9ba0 100644
--- a/crates/cargo-contract/src/cmd/verify.rs
+++ b/crates/cargo-contract/src/cmd/verify.rs
@@ -15,8 +15,15 @@
 // along with cargo-contract.  If not, see <http://www.gnu.org/licenses/>.
 
 use crate::{
-    cmd::metadata::BuildInfo,
+    cmd::{
+        build::{
+            execute,
+            ExecuteArgs,
+        },
+        metadata::BuildInfo,
+    },
     workspace::ManifestPath,
+    BuildArtifacts,
 };
 
 use anyhow::Result;
@@ -40,7 +47,7 @@ pub struct VerifyCommand {
 
 impl VerifyCommand {
     pub fn run(&self) -> Result<()> {
-        let _manifest_path = ManifestPath::try_from(self.manifest_path.as_ref())?;
+        let manifest_path = ManifestPath::try_from(self.manifest_path.as_ref())?;
 
         // 1. Read the given metadata, and pull out the `BuildInfo`
         let mut file = File::open(&self.contract)?;
@@ -54,7 +61,21 @@ impl VerifyCommand {
         dbg!(&build_info);
 
         // 2. Call `cmd::Build` with the given `BuildInfo`
-        //
+        let args = ExecuteArgs {
+            manifest_path,
+            verbosity: Default::default(),
+            build_mode: build_info.build_mode,
+            network: Default::default(),
+            build_artifact: BuildArtifacts::CodeOnly,
+            unstable_flags: Default::default(),
+            optimization_passes: build_info.wasm_opt_settings.optimization_passes,
+            keep_debug_symbols: false, /* TODO: Will either want to add this to BuildInfo or assume release (so no) */
+            skip_linting: true,
+            output_type: Default::default(),
+        };
+
+        let _build_result = execute(args)?;
+
         // 3. Read output file, compare with given contract_wasm
         todo!()
     }

From 7de595c5d9d79db42a5141fe82042ca1aec1470c Mon Sep 17 00:00:00 2001
From: Hernando Castano <hernando@hcastano.com>
Date: Thu, 11 Aug 2022 13:17:37 -0400
Subject: [PATCH 04/21] Check built Wasm file against that in the reference
 metadata

---
 crates/cargo-contract/src/cmd/verify.rs | 39 ++++++++++++++++++++++---
 1 file changed, 35 insertions(+), 4 deletions(-)

diff --git a/crates/cargo-contract/src/cmd/verify.rs b/crates/cargo-contract/src/cmd/verify.rs
index b87ac9ba0..42a899e97 100644
--- a/crates/cargo-contract/src/cmd/verify.rs
+++ b/crates/cargo-contract/src/cmd/verify.rs
@@ -58,11 +58,10 @@ impl VerifyCommand {
         let build_info = metadata.source.build_info.as_ref().unwrap();
         let build_info: BuildInfo =
             serde_json::from_value(build_info.clone().into()).unwrap();
-        dbg!(&build_info);
 
         // 2. Call `cmd::Build` with the given `BuildInfo`
         let args = ExecuteArgs {
-            manifest_path,
+            manifest_path: manifest_path.clone(),
             verbosity: Default::default(),
             build_mode: build_info.build_mode,
             network: Default::default(),
@@ -74,9 +73,41 @@ impl VerifyCommand {
             output_type: Default::default(),
         };
 
-        let _build_result = execute(args)?;
+        let build_result = execute(args)?;
 
         // 3. Read output file, compare with given contract_wasm
-        todo!()
+        let reference_wasm = metadata.source.wasm.unwrap().to_string();
+
+        let built_wasm_path = build_result.dest_wasm.unwrap();
+        let fs_wasm = std::fs::read(built_wasm_path)?;
+        let built_wasm = build_byte_str(&fs_wasm);
+
+        if reference_wasm != built_wasm {
+            log::debug!(
+                "Expected Wasm Binary '{}'\n\nGot Wasm Binary `{}`",
+                &reference_wasm,
+                &built_wasm
+            );
+            anyhow::bail!(
+                "Failed to verify the authenticity of `{}` contract againt the workspace found at {:?}.",
+                metadata.contract.name,
+                manifest_path.as_ref(),
+            );
+        }
+
+        log::info!("Succesfully verified `{}`!", &metadata.contract.name);
+
+        Ok(())
+    }
+}
+
+fn build_byte_str(bytes: &[u8]) -> String {
+    use std::fmt::Write;
+
+    let mut str = String::new();
+    write!(str, "0x").expect("failed writing to string");
+    for byte in bytes {
+        write!(str, "{:02x}", byte).expect("failed writing to string");
     }
+    str
 }

From e67d108a0651eab7a8ab7b1fa0f0c3d3eea1d53c Mon Sep 17 00:00:00 2001
From: Hernando Castano <hernando@hcastano.com>
Date: Thu, 11 Aug 2022 13:30:11 -0400
Subject: [PATCH 05/21] Comopare `SourceWasm`'s instead of byte strings

---
 crates/cargo-contract/src/cmd/verify.rs | 21 +++++++--------------
 crates/metadata/src/lib.rs              |  2 +-
 2 files changed, 8 insertions(+), 15 deletions(-)

diff --git a/crates/cargo-contract/src/cmd/verify.rs b/crates/cargo-contract/src/cmd/verify.rs
index 42a899e97..b45c8855f 100644
--- a/crates/cargo-contract/src/cmd/verify.rs
+++ b/crates/cargo-contract/src/cmd/verify.rs
@@ -27,7 +27,10 @@ use crate::{
 };
 
 use anyhow::Result;
-use contract_metadata::ContractMetadata;
+use contract_metadata::{
+    ContractMetadata,
+    SourceWasm,
+};
 
 use std::{
     fs::File,
@@ -76,11 +79,11 @@ impl VerifyCommand {
         let build_result = execute(args)?;
 
         // 3. Read output file, compare with given contract_wasm
-        let reference_wasm = metadata.source.wasm.unwrap().to_string();
+        let reference_wasm = metadata.source.wasm.unwrap();
 
         let built_wasm_path = build_result.dest_wasm.unwrap();
         let fs_wasm = std::fs::read(built_wasm_path)?;
-        let built_wasm = build_byte_str(&fs_wasm);
+        let built_wasm = SourceWasm::new(fs_wasm);
 
         if reference_wasm != built_wasm {
             log::debug!(
@@ -88,6 +91,7 @@ impl VerifyCommand {
                 &reference_wasm,
                 &built_wasm
             );
+
             anyhow::bail!(
                 "Failed to verify the authenticity of `{}` contract againt the workspace found at {:?}.",
                 metadata.contract.name,
@@ -100,14 +104,3 @@ impl VerifyCommand {
         Ok(())
     }
 }
-
-fn build_byte_str(bytes: &[u8]) -> String {
-    use std::fmt::Write;
-
-    let mut str = String::new();
-    write!(str, "0x").expect("failed writing to string");
-    for byte in bytes {
-        write!(str, "{:02x}", byte).expect("failed writing to string");
-    }
-    str
-}
diff --git a/crates/metadata/src/lib.rs b/crates/metadata/src/lib.rs
index 4735dabaf..41786bbf2 100644
--- a/crates/metadata/src/lib.rs
+++ b/crates/metadata/src/lib.rs
@@ -166,7 +166,7 @@ impl Source {
 }
 
 /// The bytes of the compiled Wasm smart contract.
-#[derive(Clone, Debug, Deserialize, Serialize)]
+#[derive(Clone, Debug, Deserialize, Serialize, PartialEq, Eq)]
 pub struct SourceWasm(
     #[serde(
         serialize_with = "byte_str::serialize_as_byte_str",

From b90f12639a009fe87dee6cb1078d9b6f5469bedb Mon Sep 17 00:00:00 2001
From: Hernando Castano <hernando@hcastano.com>
Date: Mon, 15 Aug 2022 13:46:51 -0400
Subject: [PATCH 06/21] Check that current `nightly` matches that from contract

---
 crates/cargo-contract/src/cmd/verify.rs | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/crates/cargo-contract/src/cmd/verify.rs b/crates/cargo-contract/src/cmd/verify.rs
index b45c8855f..4e92c1d3a 100644
--- a/crates/cargo-contract/src/cmd/verify.rs
+++ b/crates/cargo-contract/src/cmd/verify.rs
@@ -63,6 +63,23 @@ impl VerifyCommand {
             serde_json::from_value(build_info.clone().into()).unwrap();
 
         // 2. Call `cmd::Build` with the given `BuildInfo`
+        let expected_rustc_version = build_info.rustc_version;
+        let rustc_version = rustc_version::version_meta()?;
+        let rustc_version = format!(
+            "{:?}-{}",
+            rustc_version.channel,
+            rustc_version.commit_date.expect("TODO")
+        )
+        .to_lowercase();
+
+        anyhow::ensure!(
+            rustc_version == expected_rustc_version,
+            "You are trying to `verify` a contract using the `{rustc_version}` toolchain.\n\
+             However, the original contract was built using `{expected_rustc_version}`. Please\n\
+             install the correct toolchain (`rustup install {expected_rustc_version}`) and\n\
+             re-run the `verify` command.",
+        );
+
         let args = ExecuteArgs {
             manifest_path: manifest_path.clone(),
             verbosity: Default::default(),

From a350f4c5d57da0d264f1252ae901928108e4f407 Mon Sep 17 00:00:00 2001
From: Hernando Castano <hernando@hcastano.com>
Date: Thu, 18 Aug 2022 16:20:03 -0400
Subject: [PATCH 07/21] Switch from `env_logger` to `tracing`

---
 crates/cargo-contract/src/cmd/verify.rs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/crates/cargo-contract/src/cmd/verify.rs b/crates/cargo-contract/src/cmd/verify.rs
index 4e92c1d3a..bf8c1e979 100644
--- a/crates/cargo-contract/src/cmd/verify.rs
+++ b/crates/cargo-contract/src/cmd/verify.rs
@@ -103,7 +103,7 @@ impl VerifyCommand {
         let built_wasm = SourceWasm::new(fs_wasm);
 
         if reference_wasm != built_wasm {
-            log::debug!(
+            tracing::debug!(
                 "Expected Wasm Binary '{}'\n\nGot Wasm Binary `{}`",
                 &reference_wasm,
                 &built_wasm
@@ -116,7 +116,7 @@ impl VerifyCommand {
             );
         }
 
-        log::info!("Succesfully verified `{}`!", &metadata.contract.name);
+        tracing::info!("Succesfully verified `{}`!", &metadata.contract.name);
 
         Ok(())
     }

From e87c51a8639f056c7c5db18e125adca998be91ac Mon Sep 17 00:00:00 2001
From: Hernando Castano <hernando@hcastano.com>
Date: Thu, 18 Aug 2022 16:21:23 -0400
Subject: [PATCH 08/21] Use helper function to get current Rust toolchain

---
 crates/cargo-contract/src/cmd/verify.rs | 8 +-------
 1 file changed, 1 insertion(+), 7 deletions(-)

diff --git a/crates/cargo-contract/src/cmd/verify.rs b/crates/cargo-contract/src/cmd/verify.rs
index bf8c1e979..f6c5f70d5 100644
--- a/crates/cargo-contract/src/cmd/verify.rs
+++ b/crates/cargo-contract/src/cmd/verify.rs
@@ -64,13 +64,7 @@ impl VerifyCommand {
 
         // 2. Call `cmd::Build` with the given `BuildInfo`
         let expected_rustc_version = build_info.rustc_version;
-        let rustc_version = rustc_version::version_meta()?;
-        let rustc_version = format!(
-            "{:?}-{}",
-            rustc_version.channel,
-            rustc_version.commit_date.expect("TODO")
-        )
-        .to_lowercase();
+        let rustc_version = crate::util::rustc_toolchain()?;
 
         anyhow::ensure!(
             rustc_version == expected_rustc_version,

From 4317f550892051b036104215286e14778dba2460 Mon Sep 17 00:00:00 2001
From: Hernando Castano <hernando@hcastano.com>
Date: Thu, 18 Aug 2022 16:27:54 -0400
Subject: [PATCH 09/21] Clean up docs a little

---
 crates/cargo-contract/src/cmd/verify.rs | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/crates/cargo-contract/src/cmd/verify.rs b/crates/cargo-contract/src/cmd/verify.rs
index f6c5f70d5..c90d61a36 100644
--- a/crates/cargo-contract/src/cmd/verify.rs
+++ b/crates/cargo-contract/src/cmd/verify.rs
@@ -38,6 +38,7 @@ use std::{
     path::PathBuf,
 };
 
+/// Checks if a contract in the given workspace matches that of a reference contract.
 #[derive(Debug, clap::Args)]
 #[clap(name = "verify")]
 pub struct VerifyCommand {
@@ -62,7 +63,7 @@ impl VerifyCommand {
         let build_info: BuildInfo =
             serde_json::from_value(build_info.clone().into()).unwrap();
 
-        // 2. Call `cmd::Build` with the given `BuildInfo`
+        // 2. Call `cargo contract build` with the `BuildInfo` from the metadata.
         let expected_rustc_version = build_info.rustc_version;
         let rustc_version = crate::util::rustc_toolchain()?;
 
@@ -89,7 +90,7 @@ impl VerifyCommand {
 
         let build_result = execute(args)?;
 
-        // 3. Read output file, compare with given contract_wasm
+        // 3. Grab the built Wasm contract and compare it with the Wasm from the metadata.
         let reference_wasm = metadata.source.wasm.unwrap();
 
         let built_wasm_path = build_result.dest_wasm.unwrap();

From fed9c3ffa46469312ad93499001f506b40ba112d Mon Sep 17 00:00:00 2001
From: Hernando Castano <hernando@hcastano.com>
Date: Fri, 19 Aug 2022 16:43:34 -0400
Subject: [PATCH 10/21] Bail out if `wasm-opt` versions don't match

This should maybe be a warning instead of an error, but I'll need
to experiment with this more.
---
 crates/cargo-contract/src/cmd/verify.rs | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/crates/cargo-contract/src/cmd/verify.rs b/crates/cargo-contract/src/cmd/verify.rs
index c90d61a36..6ae1a4f7b 100644
--- a/crates/cargo-contract/src/cmd/verify.rs
+++ b/crates/cargo-contract/src/cmd/verify.rs
@@ -75,6 +75,22 @@ impl VerifyCommand {
              re-run the `verify` command.",
         );
 
+        let expected_wasm_opt_version = build_info.wasm_opt_settings.version;
+        // TODO: Will either want to add this to BuildInfo or assume release (so no)
+        let keep_debug_symbols = false;
+        let handler = crate::wasm_opt::WasmOptHandler::new(
+            build_info.wasm_opt_settings.optimization_passes,
+            keep_debug_symbols,
+        )?;
+        let wasm_opt_version = handler.version();
+
+        anyhow::ensure!(
+            wasm_opt_version == expected_wasm_opt_version,
+            "You are trying to `verify` a contract using `wasm-opt` version {wasm_opt_version}`.\n\
+             However, the original contract was built using `wasm-opt` version {expected_wasm_opt_version}`.\n\
+             Please install the matching version and re-run the `verify` command.",
+        );
+
         let args = ExecuteArgs {
             manifest_path: manifest_path.clone(),
             verbosity: Default::default(),
@@ -83,7 +99,7 @@ impl VerifyCommand {
             build_artifact: BuildArtifacts::CodeOnly,
             unstable_flags: Default::default(),
             optimization_passes: build_info.wasm_opt_settings.optimization_passes,
-            keep_debug_symbols: false, /* TODO: Will either want to add this to BuildInfo or assume release (so no) */
+            keep_debug_symbols,
             skip_linting: true,
             output_type: Default::default(),
         };

From b74398730df990d044f039254f3a25db470070d6 Mon Sep 17 00:00:00 2001
From: Hernando Castano <hernando@hcastano.com>
Date: Mon, 29 Aug 2022 15:09:08 -0400
Subject: [PATCH 11/21] Use stable `rustc` toolchain

---
 crates/cargo-contract/src/cmd/verify.rs | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/crates/cargo-contract/src/cmd/verify.rs b/crates/cargo-contract/src/cmd/verify.rs
index 6ae1a4f7b..a04418b26 100644
--- a/crates/cargo-contract/src/cmd/verify.rs
+++ b/crates/cargo-contract/src/cmd/verify.rs
@@ -65,7 +65,8 @@ impl VerifyCommand {
 
         // 2. Call `cargo contract build` with the `BuildInfo` from the metadata.
         let expected_rustc_version = build_info.rustc_version;
-        let rustc_version = crate::util::rustc_toolchain()?;
+        let rustc_version = rustc_version::version()
+            .expect("`rustc` always has a version associated with it.");
 
         anyhow::ensure!(
             rustc_version == expected_rustc_version,

From f6770dedf217997d52fcc45ed0cc946bc6ecf3a9 Mon Sep 17 00:00:00 2001
From: Hernando Castano <hernando@hcastano.com>
Date: Thu, 29 Sep 2022 16:42:08 -0400
Subject: [PATCH 12/21] Use `keep_debug_symbols` from metadata

---
 crates/cargo-contract/src/cmd/verify.rs | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/crates/cargo-contract/src/cmd/verify.rs b/crates/cargo-contract/src/cmd/verify.rs
index a04418b26..591a5e415 100644
--- a/crates/cargo-contract/src/cmd/verify.rs
+++ b/crates/cargo-contract/src/cmd/verify.rs
@@ -77,8 +77,7 @@ impl VerifyCommand {
         );
 
         let expected_wasm_opt_version = build_info.wasm_opt_settings.version;
-        // TODO: Will either want to add this to BuildInfo or assume release (so no)
-        let keep_debug_symbols = false;
+        let keep_debug_symbols = build_info.wasm_opt_settings.keep_debug_symbols;
         let handler = crate::wasm_opt::WasmOptHandler::new(
             build_info.wasm_opt_settings.optimization_passes,
             keep_debug_symbols,

From 2f3ca03a0d3ed6cd9b2f8e9ae1d773628962abf2 Mon Sep 17 00:00:00 2001
From: Hernando Castano <hernando@hcastano.com>
Date: Thu, 29 Sep 2022 16:42:19 -0400
Subject: [PATCH 13/21] Make output more colourful

---
 crates/cargo-contract/src/cmd/verify.rs | 27 ++++++++++++++++++-------
 1 file changed, 20 insertions(+), 7 deletions(-)

diff --git a/crates/cargo-contract/src/cmd/verify.rs b/crates/cargo-contract/src/cmd/verify.rs
index 591a5e415..ce701eb4d 100644
--- a/crates/cargo-contract/src/cmd/verify.rs
+++ b/crates/cargo-contract/src/cmd/verify.rs
@@ -22,11 +22,14 @@ use crate::{
         },
         metadata::BuildInfo,
     },
+    maybe_println,
     workspace::ManifestPath,
     BuildArtifacts,
+    Verbosity,
+    VerbosityFlags,
 };
-
 use anyhow::Result;
+use colored::Colorize;
 use contract_metadata::{
     ContractMetadata,
     SourceWasm,
@@ -47,11 +50,15 @@ pub struct VerifyCommand {
     manifest_path: Option<PathBuf>,
     /// The reference Wasm contract (`*.contract`) that the workspace will be checked against.
     contract: PathBuf,
+    ///
+    #[clap(flatten)]
+    verbosity: VerbosityFlags,
 }
 
 impl VerifyCommand {
     pub fn run(&self) -> Result<()> {
         let manifest_path = ManifestPath::try_from(self.manifest_path.as_ref())?;
+        let verbosity: Verbosity = TryFrom::<&VerbosityFlags>::try_from(&self.verbosity)?;
 
         // 1. Read the given metadata, and pull out the `BuildInfo`
         let mut file = File::open(&self.contract)?;
@@ -93,7 +100,7 @@ impl VerifyCommand {
 
         let args = ExecuteArgs {
             manifest_path: manifest_path.clone(),
-            verbosity: Default::default(),
+            verbosity,
             build_mode: build_info.build_mode,
             network: Default::default(),
             build_artifact: BuildArtifacts::CodeOnly,
@@ -120,14 +127,20 @@ impl VerifyCommand {
                 &built_wasm
             );
 
-            anyhow::bail!(
-                "Failed to verify the authenticity of `{}` contract againt the workspace found at {:?}.",
-                metadata.contract.name,
-                manifest_path.as_ref(),
+            anyhow::bail!(format!(
+                "\nFailed to verify the authenticity of {} contract againt the workspace \n\
+                found at {}.",
+                format!("`{}`", metadata.contract.name).bright_white(),
+                format!("{:?}", manifest_path.as_ref()).bright_white()).bright_red()
             );
         }
 
-        tracing::info!("Succesfully verified `{}`!", &metadata.contract.name);
+        maybe_println!(
+            verbosity,
+            " \n{} {}",
+            "Succesfully verified contract".bright_green().bold(),
+            format!("`{}`!", &metadata.contract.name).bold(),
+        );
 
         Ok(())
     }

From e2c567565bb893e01396d820cafbd0e9bd963861 Mon Sep 17 00:00:00 2001
From: Hernando Castano <hernando@hcastano.com>
Date: Thu, 29 Sep 2022 16:43:51 -0400
Subject: [PATCH 14/21] Add missing doc comment

---
 crates/cargo-contract/src/cmd/verify.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/crates/cargo-contract/src/cmd/verify.rs b/crates/cargo-contract/src/cmd/verify.rs
index ce701eb4d..f358945bc 100644
--- a/crates/cargo-contract/src/cmd/verify.rs
+++ b/crates/cargo-contract/src/cmd/verify.rs
@@ -50,7 +50,7 @@ pub struct VerifyCommand {
     manifest_path: Option<PathBuf>,
     /// The reference Wasm contract (`*.contract`) that the workspace will be checked against.
     contract: PathBuf,
-    ///
+    /// Denotes if output should be printed to stdout.
     #[clap(flatten)]
     verbosity: VerbosityFlags,
 }

From 963387cad260401b290394cdabfcb5de2b63e9ff Mon Sep 17 00:00:00 2001
From: Hernando Castano <hernando@hcastano.com>
Date: Thu, 29 Sep 2022 17:23:01 -0400
Subject: [PATCH 15/21] Do a better job of error handling

---
 crates/cargo-contract/src/cmd/verify.rs | 64 +++++++++++++++++++------
 1 file changed, 50 insertions(+), 14 deletions(-)

diff --git a/crates/cargo-contract/src/cmd/verify.rs b/crates/cargo-contract/src/cmd/verify.rs
index f358945bc..339804190 100644
--- a/crates/cargo-contract/src/cmd/verify.rs
+++ b/crates/cargo-contract/src/cmd/verify.rs
@@ -66,22 +66,36 @@ impl VerifyCommand {
         file.read_to_string(&mut contents)?;
 
         let metadata: ContractMetadata = serde_json::from_str(&contents)?;
-        let build_info = metadata.source.build_info.as_ref().unwrap();
-        let build_info: BuildInfo =
-            serde_json::from_value(build_info.clone().into()).unwrap();
+        let build_info = if let Some(info) = metadata.source.build_info {
+            info
+        } else {
+            anyhow::bail!(
+                "\nThe metadata does not contain any build information which can be used to \
+                verify a contract."
+                .to_string()
+                .bright_yellow()
+            )
+        };
+
+        let build_info: BuildInfo = serde_json::from_value(build_info.clone().into())?;
+
+        tracing::debug!(
+            "Parsed the following build info from the metadata: {:?}",
+            &build_info,
+        );
 
         // 2. Call `cargo contract build` with the `BuildInfo` from the metadata.
         let expected_rustc_version = build_info.rustc_version;
         let rustc_version = rustc_version::version()
             .expect("`rustc` always has a version associated with it.");
 
-        anyhow::ensure!(
-            rustc_version == expected_rustc_version,
-            "You are trying to `verify` a contract using the `{rustc_version}` toolchain.\n\
+        let rustc_matches = rustc_version == expected_rustc_version;
+        let mismatched_rustc = format!(
+            "\nYou are trying to `verify` a contract using the `{rustc_version}` toolchain.\n\
              However, the original contract was built using `{expected_rustc_version}`. Please\n\
              install the correct toolchain (`rustup install {expected_rustc_version}`) and\n\
-             re-run the `verify` command.",
-        );
+             re-run the `verify` command.",);
+        anyhow::ensure!(rustc_matches, mismatched_rustc.bright_yellow());
 
         let expected_wasm_opt_version = build_info.wasm_opt_settings.version;
         let keep_debug_symbols = build_info.wasm_opt_settings.keep_debug_symbols;
@@ -91,12 +105,13 @@ impl VerifyCommand {
         )?;
         let wasm_opt_version = handler.version();
 
-        anyhow::ensure!(
-            wasm_opt_version == expected_wasm_opt_version,
-            "You are trying to `verify` a contract using `wasm-opt` version {wasm_opt_version}`.\n\
-             However, the original contract was built using `wasm-opt` version {expected_wasm_opt_version}`.\n\
+        let wasm_opt_matches = wasm_opt_version == expected_wasm_opt_version;
+        let mismatched_wasm_opt = format!(
+            "\nYou are trying to `verify` a contract using `wasm-opt` version `{wasm_opt_version}`.\n\
+             However, the original contract was built using `wasm-opt` version `{expected_wasm_opt_version}`.\n\
              Please install the matching version and re-run the `verify` command.",
         );
+        anyhow::ensure!(wasm_opt_matches, mismatched_wasm_opt.bright_yellow());
 
         let args = ExecuteArgs {
             manifest_path: manifest_path.clone(),
@@ -114,9 +129,30 @@ impl VerifyCommand {
         let build_result = execute(args)?;
 
         // 3. Grab the built Wasm contract and compare it with the Wasm from the metadata.
-        let reference_wasm = metadata.source.wasm.unwrap();
+        let reference_wasm = if let Some(wasm) = metadata.source.wasm {
+            wasm
+        } else {
+            anyhow::bail!(
+                "\nThe metadata for the reference contract does not contain a Wasm binary,\n\
+                therefore we are unable to verify the contract."
+                .to_string()
+                .bright_yellow()
+            )
+        };
+
+        let built_wasm_path = if let Some(wasm) = build_result.dest_wasm {
+            wasm
+        } else {
+            // Since we're building the contract ourselves this should always be populated,
+            // but we'll bail out here just in case.
+            anyhow::bail!(
+                "\nThe metadata for the workspace contract does not contain a Wasm binary,\n\
+                therefore we are unable to verify the contract."
+                .to_string()
+                .bright_yellow()
+            )
+        };
 
-        let built_wasm_path = build_result.dest_wasm.unwrap();
         let fs_wasm = std::fs::read(built_wasm_path)?;
         let built_wasm = SourceWasm::new(fs_wasm);
 

From e7b957783fc283375273ed8f4e735b2247795834 Mon Sep 17 00:00:00 2001
From: Hernando Castano <hernando@hcastano.com>
Date: Thu, 29 Sep 2022 17:36:01 -0400
Subject: [PATCH 16/21] Add more error handling improvements

---
 crates/cargo-contract/src/cmd/verify.rs | 22 +++++++++++++++-------
 1 file changed, 15 insertions(+), 7 deletions(-)

diff --git a/crates/cargo-contract/src/cmd/verify.rs b/crates/cargo-contract/src/cmd/verify.rs
index 339804190..45fc76c08 100644
--- a/crates/cargo-contract/src/cmd/verify.rs
+++ b/crates/cargo-contract/src/cmd/verify.rs
@@ -28,7 +28,10 @@ use crate::{
     Verbosity,
     VerbosityFlags,
 };
-use anyhow::Result;
+use anyhow::{
+    Context,
+    Result,
+};
 use colored::Colorize;
 use contract_metadata::{
     ContractMetadata,
@@ -37,7 +40,6 @@ use contract_metadata::{
 
 use std::{
     fs::File,
-    io::prelude::Read,
     path::PathBuf,
 };
 
@@ -61,11 +63,13 @@ impl VerifyCommand {
         let verbosity: Verbosity = TryFrom::<&VerbosityFlags>::try_from(&self.verbosity)?;
 
         // 1. Read the given metadata, and pull out the `BuildInfo`
-        let mut file = File::open(&self.contract)?;
-        let mut contents = String::new();
-        file.read_to_string(&mut contents)?;
+        let path = &self.contract;
+        let file = File::open(path)
+            .context(format!("Failed to open contract bundle {}", path.display()))?;
 
-        let metadata: ContractMetadata = serde_json::from_str(&contents)?;
+        let metadata: ContractMetadata = serde_json::from_reader(&file).context(
+            format!("Failed to deserialize contract bundle {}", path.display()),
+        )?;
         let build_info = if let Some(info) = metadata.source.build_info {
             info
         } else {
@@ -77,7 +81,11 @@ impl VerifyCommand {
             )
         };
 
-        let build_info: BuildInfo = serde_json::from_value(build_info.clone().into())?;
+        let build_info: BuildInfo = serde_json::from_value(build_info.clone().into())
+            .context(format!(
+                "Failed to deserialize the build info from {}",
+                path.display()
+            ))?;
 
         tracing::debug!(
             "Parsed the following build info from the metadata: {:?}",

From a64b631d919a24d03c936e01ee0c780aa4d0b955 Mon Sep 17 00:00:00 2001
From: Hernando Castano <hernando@hcastano.com>
Date: Thu, 29 Sep 2022 17:44:29 -0400
Subject: [PATCH 17/21] Add `CHANGELOG` entry

---
 CHANGELOG.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 126b48304..121d82466 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 - Add Rust specific build info to metadata - [#680](https://github.com/paritytech/cargo-contract/pull/680)
+- Add `verify` command - [#696](https://github.com/paritytech/cargo-contract/pull/696)
 
 ### Changed
 - Removed requirement to install binaryen. The `wasm-opt` tool is now compiled into `cargo-contract`.

From d6db73fab17ac0d8b599330ff02f0a7422ee3e00 Mon Sep 17 00:00:00 2001
From: Hernando Castano <hernando@hcastano.com>
Date: Thu, 29 Sep 2022 17:46:04 -0400
Subject: [PATCH 18/21] Appease Clippy

---
 crates/cargo-contract/src/cmd/verify.rs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/crates/cargo-contract/src/cmd/verify.rs b/crates/cargo-contract/src/cmd/verify.rs
index 45fc76c08..a92e35e96 100644
--- a/crates/cargo-contract/src/cmd/verify.rs
+++ b/crates/cargo-contract/src/cmd/verify.rs
@@ -81,8 +81,8 @@ impl VerifyCommand {
             )
         };
 
-        let build_info: BuildInfo = serde_json::from_value(build_info.clone().into())
-            .context(format!(
+        let build_info: BuildInfo =
+            serde_json::from_value(build_info.into()).context(format!(
                 "Failed to deserialize the build info from {}",
                 path.display()
             ))?;

From 80233c43d5cfd61cd64fb4c2dee263d8e51ca805 Mon Sep 17 00:00:00 2001
From: Hernando Castano <hernando@hcastano.com>
Date: Thu, 20 Oct 2022 15:22:02 -0400
Subject: [PATCH 19/21] Use updated Rust toolchain build info

---
 crates/cargo-contract/src/cmd/verify.rs | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/crates/cargo-contract/src/cmd/verify.rs b/crates/cargo-contract/src/cmd/verify.rs
index a92e35e96..773769e6b 100644
--- a/crates/cargo-contract/src/cmd/verify.rs
+++ b/crates/cargo-contract/src/cmd/verify.rs
@@ -93,15 +93,15 @@ impl VerifyCommand {
         );
 
         // 2. Call `cargo contract build` with the `BuildInfo` from the metadata.
-        let expected_rustc_version = build_info.rustc_version;
-        let rustc_version = rustc_version::version()
+        let expected_rust_toolchain = build_info.rust_toolchain;
+        let rust_toolchain = crate::util::rust_toolchain()
             .expect("`rustc` always has a version associated with it.");
 
-        let rustc_matches = rustc_version == expected_rustc_version;
+        let rustc_matches = rust_toolchain == expected_rust_toolchain;
         let mismatched_rustc = format!(
-            "\nYou are trying to `verify` a contract using the `{rustc_version}` toolchain.\n\
-             However, the original contract was built using `{expected_rustc_version}`. Please\n\
-             install the correct toolchain (`rustup install {expected_rustc_version}`) and\n\
+            "\nYou are trying to `verify` a contract using the `{rust_toolchain}` toolchain.\n\
+             However, the original contract was built using `{expected_rust_toolchain}`. Please\n\
+             install the correct toolchain (`rustup install {expected_rust_toolchain}`) and\n\
              re-run the `verify` command.",);
         anyhow::ensure!(rustc_matches, mismatched_rustc.bright_yellow());
 

From 98cc7fbb057166e7743693fc96c0591369508571 Mon Sep 17 00:00:00 2001
From: Hernando Castano <hernando@hcastano.com>
Date: Thu, 20 Oct 2022 15:48:29 -0400
Subject: [PATCH 20/21] Apply fixes for `clap` `v4.0`

---
 crates/cargo-contract/src/cmd/verify.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/crates/cargo-contract/src/cmd/verify.rs b/crates/cargo-contract/src/cmd/verify.rs
index 773769e6b..7826f9f84 100644
--- a/crates/cargo-contract/src/cmd/verify.rs
+++ b/crates/cargo-contract/src/cmd/verify.rs
@@ -48,7 +48,7 @@ use std::{
 #[clap(name = "verify")]
 pub struct VerifyCommand {
     /// Path to the `Cargo.toml` of the contract to verify.
-    #[clap(long, parse(from_os_str))]
+    #[clap(long, value_parser)]
     manifest_path: Option<PathBuf>,
     /// The reference Wasm contract (`*.contract`) that the workspace will be checked against.
     contract: PathBuf,

From b2d10c26e3bed83bbbf26cd7eadbfe7d5bfa18a2 Mon Sep 17 00:00:00 2001
From: Hernando Castano <hernando@hcastano.com>
Date: Thu, 20 Oct 2022 15:48:51 -0400
Subject: [PATCH 21/21] Compare `cargo-contract` versions instead of `wasm-opt`
 versions

Since releases of `cargo-contract` are now bundled with a `wasm-opt`
library we can assume that equal versions of `cargo-contract` contain
equal versions of `wasm-opt`.
---
 crates/cargo-contract/src/cmd/build/mod.rs |  2 +-
 crates/cargo-contract/src/cmd/verify.rs    | 37 ++++++++++++----------
 2 files changed, 22 insertions(+), 17 deletions(-)

diff --git a/crates/cargo-contract/src/cmd/build/mod.rs b/crates/cargo-contract/src/cmd/build/mod.rs
index b3fd8f429..ce51b950f 100644
--- a/crates/cargo-contract/src/cmd/build/mod.rs
+++ b/crates/cargo-contract/src/cmd/build/mod.rs
@@ -68,7 +68,7 @@ use std::{
 const MAX_MEMORY_PAGES: u32 = 16;
 
 /// Version of the currently executing `cargo-contract` binary.
-const VERSION: &str = env!("CARGO_PKG_VERSION");
+pub(crate) const VERSION: &str = env!("CARGO_PKG_VERSION");
 
 /// Arguments to use when executing `build` or `check` commands.
 #[derive(Default)]
diff --git a/crates/cargo-contract/src/cmd/verify.rs b/crates/cargo-contract/src/cmd/verify.rs
index 7826f9f84..d0f262892 100644
--- a/crates/cargo-contract/src/cmd/verify.rs
+++ b/crates/cargo-contract/src/cmd/verify.rs
@@ -19,6 +19,7 @@ use crate::{
         build::{
             execute,
             ExecuteArgs,
+            VERSION,
         },
         metadata::BuildInfo,
     },
@@ -92,7 +93,7 @@ impl VerifyCommand {
             &build_info,
         );
 
-        // 2. Call `cargo contract build` with the `BuildInfo` from the metadata.
+        // 2. Check that the build info from the metadata matches our current setup.
         let expected_rust_toolchain = build_info.rust_toolchain;
         let rust_toolchain = crate::util::rust_toolchain()
             .expect("`rustc` always has a version associated with it.");
@@ -105,22 +106,26 @@ impl VerifyCommand {
              re-run the `verify` command.",);
         anyhow::ensure!(rustc_matches, mismatched_rustc.bright_yellow());
 
-        let expected_wasm_opt_version = build_info.wasm_opt_settings.version;
-        let keep_debug_symbols = build_info.wasm_opt_settings.keep_debug_symbols;
-        let handler = crate::wasm_opt::WasmOptHandler::new(
-            build_info.wasm_opt_settings.optimization_passes,
-            keep_debug_symbols,
-        )?;
-        let wasm_opt_version = handler.version();
-
-        let wasm_opt_matches = wasm_opt_version == expected_wasm_opt_version;
-        let mismatched_wasm_opt = format!(
-            "\nYou are trying to `verify` a contract using `wasm-opt` version `{wasm_opt_version}`.\n\
-             However, the original contract was built using `wasm-opt` version `{expected_wasm_opt_version}`.\n\
+        let expected_cargo_contract_version = build_info.cargo_contract_version;
+        let cargo_contract_version = semver::Version::parse(VERSION)?;
+
+        // Note, assuming both versions of `cargo-contract` were installed with the same lockfile
+        // (e.g `--locked`) then the versions of `wasm-opt` should also match.
+        let cargo_contract_matches =
+            cargo_contract_version == expected_cargo_contract_version;
+        let mismatched_cargo_contract = format!(
+            "\nYou are trying to `verify` a contract using `cargo-contract` version \
+            `{cargo_contract_version}`.\n\
+             However, the original contract was built using `cargo-contract` version \
+             `{expected_cargo_contract_version}`.\n\
              Please install the matching version and re-run the `verify` command.",
         );
-        anyhow::ensure!(wasm_opt_matches, mismatched_wasm_opt.bright_yellow());
+        anyhow::ensure!(
+            cargo_contract_matches,
+            mismatched_cargo_contract.bright_yellow()
+        );
 
+        // 3. Call `cargo contract build` with the `BuildInfo` from the metadata.
         let args = ExecuteArgs {
             manifest_path: manifest_path.clone(),
             verbosity,
@@ -129,14 +134,14 @@ impl VerifyCommand {
             build_artifact: BuildArtifacts::CodeOnly,
             unstable_flags: Default::default(),
             optimization_passes: build_info.wasm_opt_settings.optimization_passes,
-            keep_debug_symbols,
+            keep_debug_symbols: build_info.wasm_opt_settings.keep_debug_symbols,
             skip_linting: true,
             output_type: Default::default(),
         };
 
         let build_result = execute(args)?;
 
-        // 3. Grab the built Wasm contract and compare it with the Wasm from the metadata.
+        // 4. Grab the built Wasm contract and compare it with the Wasm from the metadata.
         let reference_wasm = if let Some(wasm) = metadata.source.wasm {
             wasm
         } else {