feat: add inspect for builders command

Cargo.toml

@@ -55,6 +55,7 @@ shell-words = "1.1.0"
 subst = "0.3.8"
 path-slash = "0.2.1"
 jobslot = "0.2.23"
+ptree = { version = "0.5.2", default-features = false }
 
 [profile.release]
 lto = "fat"

src/cli.rs

@@ -196,6 +196,20 @@ pub fn clap() -> clap::Command {
                 .arg(define())
                 .add(SubcommandCandidates::new(task_completer)),
         )
+        .subcommand(
+            Command::new("inspect")
+                .about("inspect current configuration")
+                .arg(build_dir())
+                .subcommand(
+                    Command::new("builders").arg(
+                        Arg::new("tree")
+                            .short('t')
+                            .long("tree")
+                            .help("output a tree of the configuration builders")
+                            .action(ArgAction::SetTrue),
+                    ),
+                ),
+        )
         .subcommand(
             Command::new("clean")
                 .about("clean current configuration")

src/inspect.rs

@@ -0,0 +1,43 @@
+//! Inspect Laze project files, without any build output
+
+use std::io::Write;
+
+use anyhow::Result;
+use camino::Utf8PathBuf;
+use ptree::{write_tree, TreeBuilder};
+
+use crate::{data::load, Context, ContextBag};
+
+pub(crate) struct BuildInspector {
+    contexts: ContextBag,
+}
+
+impl BuildInspector {
+    pub(crate) fn from_project(project_file: Utf8PathBuf, build_dir: Utf8PathBuf) -> Result<Self> {
+        let (contexts, _, _) = load(&project_file, &build_dir)?;
+        Ok(Self { contexts })
+    }
+    pub(crate) fn inspect_builders(&self) -> Vec<&Context> {
+        self.contexts.builders_vec()
+    }
+
+    fn add_tree_element(&self, context: &Context, tree: &mut TreeBuilder) {
+        self.contexts
+            .contexts
+            .iter()
+            .filter(|c| Some(context) == c.get_parent(&self.contexts))
+            .for_each(|c| {
+                tree.begin_child(c.name.to_string());
+                self.add_tree_element(c, tree);
+                tree.end_child();
+            })
+    }
+
+    pub(crate) fn write_tree<W: Write>(&self, w: W) -> Result<()> {
+        let default = self.contexts.get_by_name(&"default".to_string()).unwrap();
+        let mut tree_builder = TreeBuilder::new("default".to_string()); // The first node is always called default
+        self.add_tree_element(default, &mut tree_builder);
+        let tree = tree_builder.build();
+        write_tree(&tree, w).map_err(|e| e.into())
+    }
+}