CLI if genhtml is not installed

src/bin/anchor-coverage.rs

@@ -2,8 +2,8 @@ use anchor_coverage::util::StripCurrentDir;
 use anyhow::{bail, ensure, Result};
 use std::{
     env::{args, current_dir},
-    fs::{canonicalize, create_dir_all, remove_dir_all},
-    path::{Path, PathBuf},
+    fs::{create_dir_all, remove_dir_all},
+    path::Path,
     process::Command,
 };
 
@@ -127,18 +127,9 @@ fn anchor_test_skip_build(args: &[String], sbf_trace_dir: &Path) -> Result<()> {
 }
 
 fn grep_command() -> Result<String> {
-    let path = which("solana-test-validator")?;
+    let path = anchor_coverage::util::which("solana-test-validator")?;
     Ok(format!(
         "grep SBF_TRACE_DIR {} || echo 'solana-test-validator is not patched'",
         path.display()
     ))
 }
-
-fn which(filename: &str) -> Result<PathBuf> {
-    let mut command = Command::new("which");
-    let output = command.arg(filename).output()?;
-    ensure!(output.status.success(), "command failed: {command:?}");
-    let stdout = std::str::from_utf8(&output.stdout)?;
-    let path = canonicalize(stdout.trim_end())?;
-    Ok(path)
-}

src/lib.rs

@@ -1,3 +1,4 @@
+use crate::util::which;
 use addr2line::Loader;
 use anyhow::{anyhow, Result};
 use byteorder::{LittleEndian, ReadBytesExt};
@@ -138,6 +139,17 @@ If you are done generating lcov files, try running:
         sbf_trace_dir.as_ref().strip_current_dir().display()
     );
 
+    if which("genhtml").is_err() {
+        eprintln!("However, it seems that `genhtml` is not installed on your system");
+        if cfg!(target_os = "macos") {
+            eprintln!("You can  install it using Homebrew:");
+            eprintln!("     brew install lcov");
+        } else if cfg!(target_os = "linux") {
+            eprintln!("You can install it using apt:");
+            eprintln!("     apt install lcov");
+        }
+    }
+
     Ok(())
 }
 

src/util.rs

@@ -1,4 +1,6 @@
-use anyhow::Result;
+use anyhow::{ensure, Result};
+use std::fs::canonicalize;
+use std::process::Command;
 use std::{
     env::current_dir,
     ffi::OsStr,
@@ -30,3 +32,12 @@ impl StripCurrentDir for Path {
         self.strip_prefix(current_dir).unwrap_or(self)
     }
 }
+
+pub fn which(filename: &str) -> Result<PathBuf> {
+    let mut command = Command::new("which");
+    let output = command.arg(filename).output()?;
+    ensure!(output.status.success(), "command failed: {command:?}");
+    let stdout = std::str::from_utf8(&output.stdout)?;
+    let path = canonicalize(stdout.trim_end())?;
+    Ok(path)
+}