Auto merge of #11242 - cassaundra:remove-workspace, r=epage

Clean up workspace dependencies after cargo remove

### What does this PR try to resolve?

After successful removal of an inherited dependency from a workspace member, clean up the root workspace manifest.

This PR is part of the continued working on cargo remove (#11099, see deferred work).

### How should we test and review this PR?

Make sure the tests cover all possible use cases. After posting this PR, I will post a short self-review regarding some design concerns.

### Additional information

#11194 is currently blocked on this feature.

src/bin/cargo/commands/remove.rs

@@ -1,9 +1,12 @@
 use cargo::core::dependency::DepKind;
+use cargo::core::Workspace;
 use cargo::ops::cargo_remove::remove;
 use cargo::ops::cargo_remove::RemoveOptions;
 use cargo::ops::resolve_ws;
 use cargo::util::command_prelude::*;
 use cargo::util::toml_mut::manifest::DepTable;
+use cargo::util::toml_mut::manifest::LocalManifest;
+use cargo::CargoResult;
 
 pub fn cli() -> clap::Command {
     clap::Command::new("remove")
@@ -85,6 +88,9 @@ pub fn exec(config: &mut Config, args: &ArgMatches) -> CliResult {
     remove(&options)?;
 
     if !dry_run {
+        // Clean up workspace dependencies
+        gc_workspace(&workspace, &options.dependencies)?;
+
         // Reload the workspace since we've changed dependencies
         let ws = args.workspace(config)?;
         resolve_ws(&ws)?;
@@ -114,3 +120,50 @@ fn parse_section(args: &ArgMatches) -> DepTable {
 
     table
 }
+
+/// Clean up workspace dependencies which no longer have a reference to them.
+fn gc_workspace(workspace: &Workspace<'_>, dependencies: &[String]) -> CargoResult<()> {
+    let mut manifest: toml_edit::Document =
+        cargo_util::paths::read(workspace.root_manifest())?.parse()?;
+
+    let members = workspace
+        .members()
+        .map(|p| LocalManifest::try_new(p.manifest_path()))
+        .collect::<CargoResult<Vec<_>>>()?;
+
+    for dep in dependencies {
+        if !dep_in_workspace(dep, &members) {
+            remove_workspace_dep(dep, &mut manifest);
+        }
+    }
+
+    cargo_util::paths::write(workspace.root_manifest(), manifest.to_string().as_bytes())?;
+
+    Ok(())
+}
+
+/// Get whether or not a dependency is depended upon in a workspace.
+fn dep_in_workspace(dep: &str, members: &[LocalManifest]) -> bool {
+    members.iter().any(|manifest| {
+        manifest.get_sections().iter().any(|(_, table)| {
+            table
+                .as_table_like()
+                .unwrap()
+                .get(dep)
+                .and_then(|t| t.get("workspace"))
+                .and_then(|v| v.as_bool())
+                .unwrap_or(false)
+        })
+    })
+}
+
+/// Remove a dependency from a workspace manifest.
+fn remove_workspace_dep(dep: &str, ws_manifest: &mut toml_edit::Document) {
+    if let Some(toml_edit::Item::Table(table)) = ws_manifest
+        .get_mut("workspace")
+        .and_then(|t| t.get_mut("dependencies"))
+    {
+        table.set_implicit(true);
+        table.remove(dep);
+    }
+}

src/cargo/util/toml_mut/manifest.rs

@@ -246,7 +246,7 @@ impl std::fmt::Display for Manifest {
 }
 
 /// An editable Cargo manifest that is available locally.
-#[derive(Debug)]
+#[derive(Debug, Clone)]
 pub struct LocalManifest {
     /// Path to the manifest.
     pub path: PathBuf,

tests/testsuite/cargo_remove/mod.rs

@@ -22,6 +22,9 @@ mod target;
 mod target_build;
 mod target_dev;
 mod update_lock_file;
+mod workspace;
+mod workspace_non_virtual;
+mod workspace_preserved;
 
 fn init_registry() {
     cargo_test_support::registry::init();

tests/testsuite/cargo_remove/workspace/in/Cargo.toml

@@ -0,0 +1,5 @@
+[workspace]
+members = [ "my-package" ]
+
+[workspace.dependencies]
+semver = "0.1.0"

tests/testsuite/cargo_remove/workspace/in/my-package/Cargo.toml

@@ -0,0 +1,24 @@
+[package]
+name = "my-package"
+version = "0.1.0"
+
+[[bin]]
+name = "main"
+path = "src/main.rs"
+
+[build-dependencies]
+semver = { workspace = true }
+
+[dependencies]
+docopt = "0.6"
+rustc-serialize = "0.4"
+semver = "0.1"
+toml = "0.1"
+clippy = "0.4"
+
+[dev-dependencies]
+regex = "0.1.1"
+serde = "1.0.90"
+
+[features]
+std = ["serde/std", "semver/std"]

tests/testsuite/cargo_remove/workspace/in/my-package/src/main.rs

@@ -0,0 +1 @@
+

tests/testsuite/cargo_remove/workspace/mod.rs

@@ -0,0 +1,25 @@
+use cargo_test_support::compare::assert_ui;
+use cargo_test_support::curr_dir;
+use cargo_test_support::CargoCommand;
+use cargo_test_support::Project;
+
+use crate::cargo_remove::init_registry;
+
+#[cargo_test]
+fn case() {
+    init_registry();
+    let project = Project::from_template(curr_dir!().join("in"));
+    let project_root = project.root();
+    let cwd = &project_root;
+
+    snapbox::cmd::Command::cargo_ui()
+        .arg("remove")
+        .args(["--package", "my-package", "--build", "semver"])
+        .current_dir(cwd)
+        .assert()
+        .success()
+        .stdout_matches_path(curr_dir!().join("stdout.log"))
+        .stderr_matches_path(curr_dir!().join("stderr.log"));
+
+    assert_ui().subset_matches(curr_dir!().join("out"), &project_root);
+}

tests/testsuite/cargo_remove/workspace/out/Cargo.toml

@@ -0,0 +1,2 @@
+[workspace]
+members = [ "my-package" ]

tests/testsuite/cargo_remove/workspace/out/my-package/Cargo.toml

@@ -0,0 +1,21 @@
+[package]
+name = "my-package"
+version = "0.1.0"
+
+[[bin]]
+name = "main"
+path = "src/main.rs"
+
+[dependencies]
+docopt = "0.6"
+rustc-serialize = "0.4"
+semver = "0.1"
+toml = "0.1"
+clippy = "0.4"
+
+[dev-dependencies]
+regex = "0.1.1"
+serde = "1.0.90"
+
+[features]
+std = ["serde/std", "semver/std"]

tests/testsuite/cargo_remove/workspace/out/my-package/src/main.rs

@@ -0,0 +1 @@
+

tests/testsuite/cargo_remove/workspace/stderr.log

@@ -0,0 +1,2 @@
+    Removing semver from build-dependencies
+    Updating `dummy-registry` index

tests/testsuite/cargo_remove/workspace_non_virtual/in/Cargo.toml

@@ -0,0 +1,30 @@
+[workspace]
+members = [ "my-member" ]
+
+[workspace.dependencies]
+semver = "0.1.0"
+
+[package]
+name = "my-package"
+version = "0.1.0"
+
+[[bin]]
+name = "main"
+path = "src/main.rs"
+
+[build-dependencies]
+semver = { workspace = true }
+
+[dependencies]
+docopt = "0.6"
+rustc-serialize = "0.4"
+semver = "0.1"
+toml = "0.1"
+clippy = "0.4"
+
+[dev-dependencies]
+regex = "0.1.1"
+serde = "1.0.90"
+
+[features]
+std = ["serde/std", "semver/std"]

tests/testsuite/cargo_remove/workspace_non_virtual/in/my-member/Cargo.toml

@@ -0,0 +1,6 @@
+[package]
+name = "my-member"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]

tests/testsuite/cargo_remove/workspace_non_virtual/mod.rs

@@ -0,0 +1,25 @@
+use cargo_test_support::compare::assert_ui;
+use cargo_test_support::curr_dir;
+use cargo_test_support::CargoCommand;
+use cargo_test_support::Project;
+
+use crate::cargo_remove::init_registry;
+
+#[cargo_test]
+fn case() {
+    init_registry();
+    let project = Project::from_template(curr_dir!().join("in"));
+    let project_root = project.root();
+    let cwd = &project_root;
+
+    snapbox::cmd::Command::cargo_ui()
+        .arg("remove")
+        .args(["--package", "my-package", "--build", "semver"])
+        .current_dir(cwd)
+        .assert()
+        .success()
+        .stdout_matches_path(curr_dir!().join("stdout.log"))
+        .stderr_matches_path(curr_dir!().join("stderr.log"));
+
+    assert_ui().subset_matches(curr_dir!().join("out"), &project_root);
+}

tests/testsuite/cargo_remove/workspace_non_virtual/out/Cargo.toml

@@ -0,0 +1,24 @@
+[workspace]
+members = [ "my-member" ]
+
+[package]
+name = "my-package"
+version = "0.1.0"
+
+[[bin]]
+name = "main"
+path = "src/main.rs"
+
+[dependencies]
+docopt = "0.6"
+rustc-serialize = "0.4"
+semver = "0.1"
+toml = "0.1"
+clippy = "0.4"
+
+[dev-dependencies]
+regex = "0.1.1"
+serde = "1.0.90"
+
+[features]
+std = ["serde/std", "semver/std"]

tests/testsuite/cargo_remove/workspace_non_virtual/out/my-member/Cargo.toml

@@ -0,0 +1,6 @@
+[package]
+name = "my-member"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]

tests/testsuite/cargo_remove/workspace_non_virtual/stderr.log

@@ -0,0 +1,2 @@
+    Removing semver from build-dependencies
+    Updating `dummy-registry` index

tests/testsuite/cargo_remove/workspace_preserved/in/Cargo.toml

@@ -0,0 +1,5 @@
+[workspace]
+members = [ "my-package", "my-other-package" ]
+
+[workspace.dependencies]
+semver = "0.1.0"

tests/testsuite/cargo_remove/workspace_preserved/in/my-other-package/Cargo.toml

@@ -0,0 +1,22 @@
+[package]
+name = "my-other-package"
+version = "0.1.0"
+
+[[bin]]
+name = "main"
+path = "src/main.rs"
+
+[dependencies]
+docopt = "0.6"
+rustc-serialize = "0.4"
+semver = "0.1"
+toml = "0.1"
+clippy = "0.4"
+
+[dev-dependencies]
+regex = "0.1.1"
+semver = { workspace = true }
+serde = "1.0.90"
+
+[features]
+std = ["serde/std", "semver/std"]

tests/testsuite/cargo_remove/workspace_preserved/in/my-other-package/src/main.rs

@@ -0,0 +1 @@
+

tests/testsuite/cargo_remove/workspace_preserved/in/my-package/Cargo.toml

@@ -0,0 +1,24 @@
+[package]
+name = "my-package"
+version = "0.1.0"
+
+[[bin]]
+name = "main"
+path = "src/main.rs"
+
+[build-dependencies]
+semver = { workspace = true }
+
+[dependencies]
+docopt = "0.6"
+rustc-serialize = "0.4"
+semver = "0.1"
+toml = "0.1"
+clippy = "0.4"
+
+[dev-dependencies]
+regex = "0.1.1"
+serde = "1.0.90"
+
+[features]
+std = ["serde/std", "semver/std"]

tests/testsuite/cargo_remove/workspace_preserved/in/my-package/src/main.rs

@@ -0,0 +1 @@
+

tests/testsuite/cargo_remove/workspace_preserved/mod.rs

@@ -0,0 +1,25 @@
+use cargo_test_support::compare::assert_ui;
+use cargo_test_support::curr_dir;
+use cargo_test_support::CargoCommand;
+use cargo_test_support::Project;
+
+use crate::cargo_remove::init_registry;
+
+#[cargo_test]
+fn case() {
+    init_registry();
+    let project = Project::from_template(curr_dir!().join("in"));
+    let project_root = project.root();
+    let cwd = &project_root;
+
+    snapbox::cmd::Command::cargo_ui()
+        .arg("remove")
+        .args(["--package", "my-package", "--build", "semver"])
+        .current_dir(cwd)
+        .assert()
+        .success()
+        .stdout_matches_path(curr_dir!().join("stdout.log"))
+        .stderr_matches_path(curr_dir!().join("stderr.log"));
+
+    assert_ui().subset_matches(curr_dir!().join("out"), &project_root);
+}

tests/testsuite/cargo_remove/workspace_preserved/out/Cargo.toml

@@ -0,0 +1,5 @@
+[workspace]
+members = [ "my-package", "my-other-package" ]
+
+[workspace.dependencies]
+semver = "0.1.0"

tests/testsuite/cargo_remove/workspace_preserved/out/my-other-package/Cargo.toml

@@ -0,0 +1,22 @@
+[package]
+name = "my-other-package"
+version = "0.1.0"
+
+[[bin]]
+name = "main"
+path = "src/main.rs"
+
+[dependencies]
+docopt = "0.6"
+rustc-serialize = "0.4"
+semver = "0.1"
+toml = "0.1"
+clippy = "0.4"
+
+[dev-dependencies]
+regex = "0.1.1"
+semver = { workspace = true }
+serde = "1.0.90"
+
+[features]
+std = ["serde/std", "semver/std"]

tests/testsuite/cargo_remove/workspace_preserved/out/my-other-package/src/main.rs

@@ -0,0 +1 @@
+