Auto merge of #6740 - ehuss:package-change-detection, r=alexcrichton

Stricter package change detection.

This changes it so that when `cargo package` verifies that nothing has modified any source files that it hashes the files' contents instead of checking for mtime changes.  mtimes are not always reliable.

This also changes it so that it checks *all* files in the package file. Previously it skipped files based on search rules such as the `exclude` list.

Closes #6717

Cargo.toml

@@ -59,6 +59,7 @@ termcolor = "1.0"
 toml = "0.4.2"
 url = "1.1"
 url_serde = "0.2.0"
+walkdir = "2.2"
 clap = "2.31.2"
 unicode-width = "0.1.5"
 openssl = { version = '0.10.11', optional = true }

src/cargo/ops/cargo_package.rs

@@ -1,3 +1,4 @@
+use std::collections::HashMap;
 use std::fs::{self, File};
 use std::io::prelude::*;
 use std::io::SeekFrom;
@@ -439,7 +440,7 @@ fn run_verify(ws: &Workspace<'_>, tar: &FileLock, opts: &PackageOpts<'_>) -> Car
     let id = SourceId::for_path(&dst)?;
     let mut src = PathSource::new(&dst, id, ws.config());
     let new_pkg = src.root_package()?;
-    let pkg_fingerprint = src.last_modified_file(&new_pkg)?;
+    let pkg_fingerprint = hash_all(&dst)?;
     let ws = Workspace::ephemeral(new_pkg, config, None, true)?;
 
     let exec: Arc<dyn Executor> = Arc::new(DefaultExecutor);
@@ -465,21 +466,83 @@ fn run_verify(ws: &Workspace<'_>, tar: &FileLock, opts: &PackageOpts<'_>) -> Car
     )?;
 
     // Check that `build.rs` didn't modify any files in the `src` directory.
-    let ws_fingerprint = src.last_modified_file(ws.current()?)?;
+    let ws_fingerprint = hash_all(&dst)?;
     if pkg_fingerprint != ws_fingerprint {
-        let (_, path) = ws_fingerprint;
+        let changes = report_hash_difference(&pkg_fingerprint, &ws_fingerprint);
         failure::bail!(
             "Source directory was modified by build.rs during cargo publish. \
-             Build scripts should not modify anything outside of OUT_DIR. \
-             Modified file: {}\n\n\
+             Build scripts should not modify anything outside of OUT_DIR.\n\
+             {}\n\n\
              To proceed despite this, pass the `--no-verify` flag.",
-            path.display()
+            changes
         )
     }
 
     Ok(())
 }
 
+fn hash_all(path: &Path) -> CargoResult<HashMap<PathBuf, u64>> {
+    fn wrap(path: &Path) -> CargoResult<HashMap<PathBuf, u64>> {
+        let mut result = HashMap::new();
+        let walker = walkdir::WalkDir::new(path).into_iter();
+        for entry in walker.filter_entry(|e| {
+            !(e.depth() == 1 && (e.file_name() == "target" || e.file_name() == "Cargo.lock"))
+        }) {
+            let entry = entry?;
+            let file_type = entry.file_type();
+            if file_type.is_file() {
+                let contents = fs::read(entry.path())?;
+                let hash = util::hex::hash_u64(&contents);
+                result.insert(entry.path().to_path_buf(), hash);
+            } else if file_type.is_symlink() {
+                let hash = util::hex::hash_u64(&fs::read_link(entry.path())?);
+                result.insert(entry.path().to_path_buf(), hash);
+            }
+        }
+        Ok(result)
+    }
+    let result = wrap(path).chain_err(|| format!("failed to verify output at {:?}", path))?;
+    Ok(result)
+}
+
+fn report_hash_difference(
+    orig: &HashMap<PathBuf, u64>,
+    after: &HashMap<PathBuf, u64>,
+) -> String {
+    let mut changed = Vec::new();
+    let mut removed = Vec::new();
+    for (key, value) in orig {
+        match after.get(key) {
+            Some(after_value) => {
+                if value != after_value {
+                    changed.push(key.to_string_lossy());
+                }
+            }
+            None => removed.push(key.to_string_lossy()),
+        }
+    }
+    let mut added: Vec<_> = after
+        .keys()
+        .filter(|key| !orig.contains_key(*key))
+        .map(|key| key.to_string_lossy())
+        .collect();
+    let mut result = Vec::new();
+    if !changed.is_empty() {
+        changed.sort_unstable();
+        result.push(format!("Changed: {}", changed.join("\n\t")));
+    }
+    if !added.is_empty() {
+        added.sort_unstable();
+        result.push(format!("Added: {}", added.join("\n\t")));
+    }
+    if !removed.is_empty() {
+        removed.sort_unstable();
+        result.push(format!("Removed: {}", removed.join("\n\t")));
+    }
+    assert!(!result.is_empty(), "unexpected empty change detection");
+    result.join("\n")
+}
+
 // It can often be the case that files of a particular name on one platform
 // can't actually be created on another platform. For example files with colons
 // in the name are allowed on Unix but not on Windows.

tests/testsuite/package.rs

@@ -3,12 +3,12 @@ use std::fs::File;
 use std::io::prelude::*;
 use std::path::Path;
 
+use crate::support::cargo_process;
 use crate::support::registry::Package;
 use crate::support::{
     basic_manifest, git, is_nightly, path2url, paths, project, publish::validate_crate_contents,
     registry,
 };
-use crate::support::{cargo_process, sleep_ms};
 use git2;
 
 #[test]
@@ -1201,27 +1201,24 @@ fn lock_file_and_workspace() {
 fn do_not_package_if_src_was_modified() {
     let p = project()
         .file("src/main.rs", r#"fn main() { println!("hello"); }"#)
+        .file("foo.txt", "")
+        .file("bar.txt", "")
         .file(
             "build.rs",
             r#"
-            use std::fs::File;
-            use std::io::Write;
+            use std::fs;
 
             fn main() {
-                let mut file = File::create("src/generated.txt").expect("failed to create file");
-                file.write_all(b"Hello, world of generated files.").expect("failed to write");
+                fs::write("src/generated.txt",
+                    "Hello, world of generated files."
+                ).expect("failed to create file");
+                fs::remove_file("foo.txt").expect("failed to remove");
+                fs::write("bar.txt", "updated content").expect("failed to update");
             }
         "#,
         )
         .build();
 
-    if cfg!(target_os = "macos") {
-        // MacOS has 1s resolution filesystem.
-        // If src/main.rs is created within 1s of src/generated.txt, then it
-        // won't trigger the modification check.
-        sleep_ms(1000);
-    }
-
     p.cargo("package")
         .with_status(101)
         .with_stderr_contains(
@@ -1230,7 +1227,10 @@ error: failed to verify package tarball
 
 Caused by:
   Source directory was modified by build.rs during cargo publish. \
-Build scripts should not modify anything outside of OUT_DIR. Modified file: [..]src/generated.txt
+Build scripts should not modify anything outside of OUT_DIR.
+Changed: [CWD]/target/package/foo-0.0.1/bar.txt
+Added: [CWD]/target/package/foo-0.0.1/src/generated.txt
+Removed: [CWD]/target/package/foo-0.0.1/foo.txt
 
 To proceed despite this, pass the `--no-verify` flag.",
         )