chore(forge eip712): use solar from compiler output

crates/config/src/lib.rs

@@ -957,6 +957,15 @@ impl Config {
         self.create_project(false, true)
     }
 
+    /// Same as [`Self::ephemeral_project()`] but configures the project to not emit any artifacts.
+    pub fn solar_project(&self) -> Result<Project<MultiCompiler>, SolcError> {
+        let mut project = self.ephemeral_project()?;
+        project.update_output_selection(|selection| {
+            *selection = OutputSelection::common_output_selection([]);
+        });
+        Ok(project)
+    }
+
     /// Builds mapping with additional settings profiles.
     fn additional_settings(
         &self,

crates/forge/src/cmd/eip712.rs

@@ -1,25 +1,19 @@
 use alloy_primitives::{B256, keccak256};
 use clap::{Parser, ValueHint};
 use eyre::Result;
-use foundry_cli::{
-    opts::{BuildOpts, configure_pcx},
-    utils::LoadConfig,
-};
+use foundry_cli::{opts::BuildOpts, utils::LoadConfig};
+use foundry_common::compile::ProjectCompiler;
 use serde::Serialize;
-use solar::{
-    parse::interface::Session,
-    sema::{
-        Gcx, Hir,
-        hir::StructId,
-        ty::{Ty, TyKind},
-    },
+use solar::sema::{
+    Gcx, Hir,
+    hir::StructId,
+    ty::{Ty, TyKind},
 };
 use std::{
     collections::BTreeMap,
     fmt::{Display, Formatter, Result as FmtResult, Write},
     ops::ControlFlow,
     path::{Path, PathBuf},
-    slice,
 };
 
 foundry_config::impl_figment_convert!(Eip712Args, build);
@@ -58,18 +52,10 @@ impl Display for Eip712Output {
 impl Eip712Args {
     pub fn run(self) -> Result<()> {
         let config = self.build.load_config()?;
-
-        let mut sess = Session::builder().with_stderr_emitter().build();
-        sess.dcx = sess.dcx.set_flags(|flags| flags.track_diagnostics = false);
-        let mut compiler = solar::sema::Compiler::new(sess);
-
+        let project = config.solar_project()?;
+        let mut output = ProjectCompiler::new().files([self.target_path]).compile(&project)?;
+        let compiler = output.parser_mut().solc_mut().compiler_mut();
         compiler.enter_mut(|compiler| -> Result<()> {
-            // Set up the parsing context with the project paths and sources.
-            let mut pcx = compiler.parse();
-            configure_pcx(&mut pcx, &config, None, Some(slice::from_ref(&self.target_path)))?;
-
-            // Parse and resolve
-            pcx.parse();
             let Ok(ControlFlow::Continue(())) = compiler.lower_asts() else { return Ok(()) };
             let gcx = compiler.gcx();
             let resolver = Resolver::new(gcx);
@@ -97,7 +83,13 @@ impl Eip712Args {
             Ok(())
         })?;
 
-        eyre::ensure!(compiler.sess().dcx.has_errors().is_ok(), "errors occurred");
+        // `compiler.sess()` inside of `ProjectCompileOutput` is built with `with_buffer_emitter`.
+        let diags = compiler.sess().dcx.emitted_diagnostics().unwrap();
+        if compiler.sess().dcx.has_errors().is_err() {
+            eyre::bail!("{diags}");
+        } else {
+            let _ = sh_print!("{diags}");
+        }
 
         Ok(())
     }

crates/forge/tests/cli/eip712.rs

@@ -57,6 +57,9 @@ library Structs2 {
 
     cmd.forge_fuse().args(["eip712", path.to_string_lossy().as_ref()]).assert_success().stdout_eq(
         str![[r#"
+[COMPILING_FILES] with [SOLC_VERSION]
+[SOLC_VERSION] [ELAPSED]
+No files changed, compilation skipped
 Structs.sol > Structs > Foo:
  - type: Foo(Bar bar)Art(uint256 id)Bar(Art art)
  - hash: 0x6d9b732373bd999fde4072274c752e03f7437067dd75521eb406d8edf1d30f7d
@@ -179,6 +182,9 @@ library InsideLibrary {
 
     cmd.forge_fuse().args(["eip712", path.to_string_lossy().as_ref()]).assert_success().stdout_eq(
         str![[r#"
+[COMPILING_FILES] with [SOLC_VERSION]
+[SOLC_VERSION] [ELAPSED]
+No files changed, compilation skipped
 FreeStanding:
  - type: FreeStanding(uint256 id,string name)
  - hash: 0xfb3c934b2382873277133498bde6eb3914ab323e3bef8b373ebcd423969bf1a2