feat(carog-tree): new --prune option

Author: weihanglo

src/bin/cargo/commands/tree.rs

@@ -56,6 +56,11 @@ pub fn cli() -> App {
             )
             .short("i"),
         )
+        .arg(multi_opt(
+            "prune",
+            "SPEC",
+            "Prune the given package from the display of the dependency tree",
+        ))
         .arg(opt("depth", "Maximum display depth of the dependency tree").value_name("DEPTH"))
         // Deprecated, use --prefix=none instead.
         .arg(Arg::with_name("no-indent").long("no-indent").hidden(true))
@@ -152,6 +157,16 @@ pub fn exec(config: &mut Config, args: &ArgMatches<'_>) -> CliResult {
     let (edge_kinds, no_proc_macro) = parse_edge_kinds(config, args)?;
     let graph_features = edge_kinds.contains(&EdgeKind::Feature);
 
+    let pkgs_to_prune = args.values_of("prune").map_or_else(
+        || Vec::new(),
+        |ps| {
+            let mut specs = ps.map(|p| p.to_string()).collect::<Vec<_>>();
+            specs.sort_unstable();
+            specs.dedup();
+            specs
+        },
+    );
+
     let packages = args.packages_from_flags()?;
     let mut invert = args
         .values_of("invert")
@@ -197,6 +212,7 @@ subtree of the package given to -p.\n\
         target,
         edge_kinds,
         invert,
+        pkgs_to_prune,
         prefix,
         no_dedupe,
         duplicates: args.is_present("duplicates"),

src/cargo/ops/tree/mod.rs

@@ -27,6 +27,8 @@ pub struct TreeOptions {
     /// The dependency kinds to display.
     pub edge_kinds: HashSet<EdgeKind>,
     pub invert: Vec<String>,
+    /// The packages to prune from the display of the dependency tree.
+    pub pkgs_to_prune: Vec<String>,
     /// The style of prefix for each line.
     pub prefix: Prefix,
     /// If `true`, duplicates will be repeated.
@@ -199,7 +201,19 @@ pub fn build_and_print(ws: &Workspace<'_>, opts: &TreeOptions) -> CargoResult<()
         graph.invert();
     }
 
-    print(ws.config(), opts, root_indexes, &graph)?;
+    // Packages to prune.
+    let pkgs_to_prune = opts
+        .pkgs_to_prune
+        .iter()
+        .map(|p| PackageIdSpec::parse(p))
+        .map(|r| {
+            // Provide a error message if pkgid is not within the resolved
+            // dependencies graph.
+            r.and_then(|spec| spec.query(ws_resolve.targeted_resolve.iter()).and(Ok(spec)))
+        })
+        .collect::<CargoResult<Vec<PackageIdSpec>>>()?;
+
+    print(ws.config(), opts, root_indexes, &pkgs_to_prune, &graph)?;
     Ok(())
 }
 
@@ -208,6 +222,7 @@ fn print(
     config: &Config,
     opts: &TreeOptions,
     roots: Vec<usize>,
+    pkgs_to_prune: &[PackageIdSpec],
     graph: &Graph<'_>,
 ) -> CargoResult<()> {
     let format = Pattern::new(&opts.format)
@@ -240,6 +255,7 @@ fn print(
             root_index,
             &format,
             symbols,
+            pkgs_to_prune,
             opts.prefix,
             opts.no_dedupe,
             opts.max_display_depth,
@@ -260,6 +276,7 @@ fn print_node<'a>(
     node_index: usize,
     format: &Pattern,
     symbols: &Symbols,
+    pkgs_to_prune: &[PackageIdSpec],
     prefix: Prefix,
     no_dedupe: bool,
     max_display_depth: u32,
@@ -319,6 +336,7 @@ fn print_node<'a>(
             node_index,
             format,
             symbols,
+            pkgs_to_prune,
             prefix,
             no_dedupe,
             max_display_depth,
@@ -339,6 +357,7 @@ fn print_dependencies<'a>(
     node_index: usize,
     format: &Pattern,
     symbols: &Symbols,
+    pkgs_to_prune: &[PackageIdSpec],
     prefix: Prefix,
     no_dedupe: bool,
     max_display_depth: u32,
@@ -391,6 +410,19 @@ fn print_dependencies<'a>(
                 true
             }
         })
+        .filter(|dep| {
+            // Filter out packages to prune.
+            if !pkgs_to_prune.is_empty() {
+                match graph.node(**dep) {
+                    Node::Package { package_id, .. } => {
+                        !pkgs_to_prune.iter().any(|spec| spec.matches(*package_id))
+                    }
+                    _ => true,
+                }
+            } else {
+                true
+            }
+        })
         .peekable();
 
     while let Some(dependency) = it.next() {
@@ -401,6 +433,7 @@ fn print_dependencies<'a>(
             *dependency,
             format,
             symbols,
+            pkgs_to_prune,
             prefix,
             no_dedupe,
             max_display_depth,