Add depth option

Close sfackler#60

src/main.rs

@@ -14,7 +14,7 @@ use petgraph::graph::NodeIndex;
 use petgraph::visit::EdgeRef;
 use petgraph::EdgeDirection;
 use std::collections::hash_map::Entry;
-use std::collections::{HashMap, HashSet};
+use std::collections::{HashMap, VecDeque};
 use std::path::PathBuf;
 use std::str::{self, FromStr};
 use std::rc::Rc;
@@ -64,6 +64,9 @@ struct Args {
  #[structopt(long = "no-dev-dependencies")]
  /// Skip dev dependencies.
  no_dev_dependencies: bool,
+ #[structopt(long = "depth", short = "D", value_name = "DEPTH")]
+ /// Max display depth of the dependency tree
+ depth: Option<usize>,
  #[structopt(long = "manifest-path", value_name = "PATH", parse(from_os_str))]
  /// Path to Cargo.toml
  manifest_path: Option<PathBuf>,
@@ -77,7 +80,7 @@ struct Args {
  /// Display the dependencies as a list (rather than a tree), but prefixed with the depth
  prefix_depth: bool,
  #[structopt(long = "all", short = "a")]
- /// Don't truncate dependencies that have already been displayed
+ /// Don't truncate dependencies that are farther down the dependency tree
  all: bool,
  #[structopt(long = "duplicate", short = "d")]
  /// Show only dependencies which come in multiple versions (implies -i)
@@ -231,6 +234,11 @@ fn real_main(args: Args, config: &mut Config) -> CliResult {
  package.package_id(),
  target,
  cfgs.as_ref().map(|r| &**r),
+ if args.duplicates || args.package.is_some() {
+ None
+ } else {
+ args.depth
+ },
  )?;
 
  let direction = if args.invert || args.duplicates {
@@ -255,11 +263,15 @@ fn real_main(args: Args, config: &mut Config) -> CliResult {
  if args.duplicates {
  let dups = find_duplicates(&graph);
  for dup in &dups {
- print_tree(dup, &graph, &format, direction, symbols, prefix, args.all)?;
+ print_tree(
+ dup, &graph, &format, direction, symbols, prefix, args.all, args.depth,
+ )?;
  println!();
  }
  } else {
- print_tree(&root, &graph, &format, direction, symbols, prefix, args.all)?;
+ print_tree(
+ &root, &graph, &format, direction, symbols, prefix, args.all, args.depth,
+ )?;
  }
 
  Ok(())
@@ -349,6 +361,8 @@ fn resolve<'a, 'cfg>(
 struct Node<'a> {
  id: PackageId,
  metadata: &'a ManifestMetadata,
+ depth_first_seen: usize,
+ is_duplicate: bool,
 }
 
 struct Graph<'a> {
@@ -362,6 +376,7 @@ fn build_graph<'a>(
  root: PackageId,
  target: Option<&str>,
  cfgs: Option<&[Cfg]>,
+ max_depth: Option<usize>,
 ) -> CargoResult<Graph<'a>> {
  let mut graph = Graph {
  graph: petgraph::Graph::new(),
@@ -370,12 +385,21 @@ fn build_graph<'a>(
  let node = Node {
  id: root.clone(),
  metadata: packages.get_one(root)?.manifest().metadata(),
+ depth_first_seen: 0,
+ is_duplicate: false,
  };
  graph.nodes.insert(root.clone(), graph.graph.add_node(node));
 
- let mut pending = vec![root];
+ if Some(0) == max_depth {
+ return Ok(graph);
+ }
+
+ let mut pending = VecDeque::new();
+ pending.push_back(root);
 
- while let Some(pkg_id) = pending.pop() {
+ let mut current_depth: usize = 1;
+
+ while let Some(pkg_id) = pending.pop_front() {
  let idx = graph.nodes[&pkg_id];
  let pkg = packages.get_one(pkg_id)?;
 
@@ -395,19 +419,36 @@ fn build_graph<'a>(
  };
  for dep in it {
  let dep_idx = match graph.nodes.entry(dep_id) {
- Entry::Occupied(e) => *e.get(),
+ Entry::Occupied(e) => {
+ let key = *e.get();
+
+ let mut node = &mut graph.graph[key];
+ node.is_duplicate = true;
+
+ key
+ }
  Entry::Vacant(e) => {
- pending.push(dep_id);
+ if let Some(depth) = max_depth {
+ if current_depth < depth {
+ pending.push_back(dep_id);
+ }
+ } else {
+ pending.push_back(dep_id);
+ }
+
  let node = Node {
  id: dep_id,
  metadata: packages.get_one(dep_id)?.manifest().metadata(),
+ depth_first_seen: current_depth,
+ is_duplicate: false,
  };
  *e.insert(graph.graph.add_node(node))
  }
  };
  graph.graph.add_edge(idx, dep_idx, dep.kind());
  }
  }
+ current_depth += 1;
  }
 
  Ok(graph)
@@ -421,8 +462,8 @@ fn print_tree<'a>(
  symbols: &Symbols,
  prefix: Prefix,
  all: bool,
+ max_depth: Option<usize>,
 ) -> CargoResult<()> {
- let mut visited_deps = HashSet::new();
  let mut levels_continue = vec![];
 
  let package = match graph.nodes.get(package) {
@@ -436,10 +477,10 @@ fn print_tree<'a>(
  format,
  direction,
  symbols,
- &mut visited_deps,
  &mut levels_continue,
  prefix,
  all,
+ max_depth,
  );
  Ok(())
 }
@@ -450,12 +491,13 @@ fn print_dependency<'a>(
  format: &Pattern,
  direction: EdgeDirection,
  symbols: &Symbols,
- visited_deps: &mut HashSet<PackageId>,
  levels_continue: &mut Vec<bool>,
  prefix: Prefix,
  all: bool,
+ max_depth: Option<usize>,
 ) {
- let new = all || visited_deps.insert(package.id);
+ let new = all || (!package.is_duplicate || levels_continue.len() <= package.depth_first_seen);
+
  let star = if new { "" } else { " (*)" };
 
  match prefix {
@@ -480,7 +522,7 @@ fn print_dependency<'a>(
 
  println!("{}{}", format.display(&package.id, package.metadata), star);
 
- if !new {
+ if !new || max_depth.map_or_else(|| false, |d| levels_continue.len() >= d) {
  return;
  }
 
@@ -509,10 +551,10 @@ fn print_dependency<'a>(
  format,
  direction,
  symbols,
- visited_deps,
  levels_continue,
  prefix,
  all,
+ max_depth,
  );
  print_dependency_kind(
  Kind::Build,
@@ -521,10 +563,10 @@ fn print_dependency<'a>(
  format,
  direction,
  symbols,
- visited_deps,
  levels_continue,
  prefix,
  all,
+ max_depth,
  );
  print_dependency_kind(
  Kind::Development,
@@ -533,10 +575,10 @@ fn print_dependency<'a>(
  format,
  direction,
  symbols,
- visited_deps,
  levels_continue,
  prefix,
  all,
+ max_depth,
  );
 }
 
@@ -547,10 +589,10 @@ fn print_dependency_kind<'a>(
  format: &Pattern,
  direction: EdgeDirection,
  symbols: &Symbols,
- visited_deps: &mut HashSet<PackageId>,
  levels_continue: &mut Vec<bool>,
  prefix: Prefix,
  all: bool,
+ max_depth: Option<usize>,
 ) {
  if deps.is_empty() {
  return;
@@ -584,10 +626,10 @@ fn print_dependency_kind<'a>(
  format,
  direction,
  symbols,
- visited_deps,
  levels_continue,
  prefix,
  all,
+ max_depth,
  );
  levels_continue.pop();
  }