Add --no-owns CLI flag for dependencies command

CHANGELOG.md

@@ -20,7 +20,7 @@ Please make sure to add your changes to the appropriate categories:
 
 ### Added
 
-- n/a
+- Added CLI flag `--no-owns` for `dependencies` command for filtering out "owns" edges and resulting isolated nodes.
 
 ### Changed
 

src/command/dependencies/filter.rs

@@ -233,6 +233,30 @@ impl<'a> Filter<'a> {
 
         debug_assert!(graph.contains_node(root_idx), "{}", ROOT_DROP_ERR_MSG);
 
+        if self.options.selection.no_owns {
+            // drop all "owns" edges:
+            graph.retain_edges(|graph, edge_idx| !matches!(&graph[edge_idx], Relationship::Owns));
+
+            // By removing the structural "owns" edges from the graph, that make it connected,
+            // we are likely to end up with a graph consisting of mostly individual unconnected nodes,
+            // which now basically contain no "dependency" information and thus aren't interesting to us.
+            //
+            // We thus also drop all nodes that don't have any remaining edges connected to them
+            // (with the exception of the crate's node, for reasons):
+            graph.retain_nodes(|graph, node_idx| {
+                let out_degree = graph
+                    .neighbors_directed(node_idx, Direction::Outgoing)
+                    .count();
+                let in_degree = graph
+                    .neighbors_directed(node_idx, Direction::Incoming)
+                    .count();
+
+                node_idx == root_idx || (out_degree + in_degree) > 0
+            });
+        }
+
+        debug_assert!(graph.contains_node(root_idx), "{}", ROOT_DROP_ERR_MSG);
+
         Ok(graph)
     }
 

src/command/dependencies/options.rs

@@ -107,6 +107,10 @@ pub struct SelectionOptions {
     #[clap(long = "no-modules")]
     pub no_modules: bool,
 
+    /// Filter out structural "owns" edges from graph.
+    #[clap(long = "no-owns")]
+    pub no_owns: bool,
+
     /// Filter out sysroot crates (`std`, `core` & friends) from graph.
     #[arg(long = "no-sysroot")]
     pub no_sysroot: bool,

tests/dependencies.rs

@@ -351,6 +351,16 @@ mod selection {
         );
     }
 
+    mod no_owns {
+        test_cmd!(
+            args: "dependencies \
+                    --no-owns",
+            success: true,
+            color_mode: ColorMode::Plain,
+            project: smoke
+        );
+    }
+
     mod no_traits {
         test_cmd!(
             args: "dependencies \
@@ -371,7 +381,7 @@ mod selection {
         );
     }
 
-    mod uses {
+    mod no_uses {
         test_cmd!(
             args: "dependencies \
                     --no-uses",

tests/snapshots/dependencies__help__smoke.snap

@@ -1,5 +1,6 @@
 ---
 source: tests/dependencies.rs
+assertion_line: 5
 expression: output
 snapshot_kind: text
 ---
@@ -27,6 +28,7 @@ Options:
       --no-externs                     Filter out extern items from extern crates from graph
       --no-fns                         Filter out functions (e.g. fns, async fns, const fns) from graph
       --no-modules                     Filter out modules (e.g. `mod foo`, `mod foo {}`) from graph
+      --no-owns                        Filter out structural "owns" edges from graph
       --no-sysroot                     Filter out sysroot crates (`std`, `core` & friends) from graph
       --no-traits                      Filter out traits (e.g. trait, unsafe trait) from graph
       --no-types                       Filter out types (e.g. structs, unions, enums) from graph

tests/snapshots/dependencies__selection__no_owns__smoke.snap

@@ -0,0 +1,127 @@
+---
+source: tests/dependencies.rs
+expression: output
+snapshot_kind: text
+---
+COMMAND:
+dependencies
+--no-owns
+
+STDERR:
+
+STDOUT:
+digraph {
+
+    graph [
+        label="smoke",
+        labelloc=t,
+
+        pad=0.4,
+
+        // Consider rendering the graph using a different layout algorithm, such as:
+        // [dot, neato, twopi, circo, fdp, sfdp]
+        layout=neato,
+        overlap=false,
+        splines="line",
+        rankdir=LR,
+
+        fontname="Helvetica", 
+        fontsize="36",
+    ];
+
+    node [
+        fontname="monospace",
+        fontsize="10",
+        shape="record",
+        style="filled",
+    ];
+
+    edge [
+        fontname="monospace",
+        fontsize="10",
+    ];
+
+    "alloc::fmt" [label="external mod|alloc::fmt", fillcolor="#81c169"]; // "mod" node
+    "alloc::string::String" [label="external struct|alloc::string::String", fillcolor="#81c169"]; // "struct" node
+    "bool" [label="external builtin|bool", fillcolor="#81c169"]; // "builtin" node
+    "core::cmp" [label="external mod|core::cmp", fillcolor="#81c169"]; // "mod" node
+    "core::future::future::Future" [label="external trait|core::future::future::Future", fillcolor="#81c169"]; // "trait" node
+    "core::marker::Sized" [label="external trait|core::marker::Sized", fillcolor="#81c169"]; // "trait" node
+    "core::ops" [label="external mod|core::ops", fillcolor="#81c169"]; // "mod" node
+    "i32" [label="external builtin|i32", fillcolor="#81c169"]; // "builtin" node
+    "smoke" [label="crate|smoke", fillcolor="#5397c8"]; // "crate" node
+    "smoke::derives::Dummy" [label="pub(self) struct|smoke::derives::Dummy", fillcolor="#db5367"]; // "struct" node
+    "smoke::derives::Dummy::clone" [label="pub(self) fn|smoke::derives::Dummy::clone", fillcolor="#db5367"]; // "fn" node
+    "smoke::functions::Crate" [label="pub(self) type|smoke::functions::Crate", fillcolor="#db5367"]; // "type" node
+    "smoke::functions::Local" [label="pub(self) struct|smoke::functions::Local", fillcolor="#db5367"]; // "struct" node
+    "smoke::functions::Std" [label="pub(self) type|smoke::functions::Std", fillcolor="#db5367"]; // "type" node
+    "smoke::functions::body" [label="pub(self) fn|smoke::functions::body", fillcolor="#db5367"]; // "fn" node
+    "smoke::functions::inputs" [label="pub(self) fn|smoke::functions::inputs", fillcolor="#db5367"]; // "fn" node
+    "smoke::functions::outputs" [label="pub(self) fn|smoke::functions::outputs", fillcolor="#db5367"]; // "fn" node
+    "smoke::hierarchy" [label="pub(crate) mod|smoke::hierarchy", fillcolor="#f8c04c"]; // "mod" node
+    "smoke::methods::Crate" [label="pub(self) type|smoke::methods::Crate", fillcolor="#db5367"]; // "type" node
+    "smoke::methods::Dummy::body" [label="pub(self) fn|smoke::methods::Dummy::body", fillcolor="#db5367"]; // "fn" node
+    "smoke::methods::Dummy::inputs" [label="pub(self) fn|smoke::methods::Dummy::inputs", fillcolor="#db5367"]; // "fn" node
+    "smoke::methods::Dummy::outputs" [label="pub(self) fn|smoke::methods::Dummy::outputs", fillcolor="#db5367"]; // "fn" node
+    "smoke::methods::Local" [label="pub(self) struct|smoke::methods::Local", fillcolor="#db5367"]; // "struct" node
+    "smoke::methods::Std" [label="pub(self) type|smoke::methods::Std", fillcolor="#db5367"]; // "type" node
+    "smoke::target::Target" [label="pub struct|smoke::target::Target", fillcolor="#81c169"]; // "struct" node
+    "smoke::uses" [label="pub(crate) mod|smoke::uses", fillcolor="#f8c04c"]; // "mod" node
+    "smoke::uses::cycle::node_0" [label="pub(self) mod|smoke::uses::cycle::node_0", fillcolor="#db5367"]; // "mod" node
+    "smoke::uses::cycle::node_1" [label="pub(self) mod|smoke::uses::cycle::node_1", fillcolor="#db5367"]; // "mod" node
+    "smoke::uses::cycle::node_1::node_2" [label="pub(self) mod|smoke::uses::cycle::node_1::node_2", fillcolor="#db5367"]; // "mod" node
+    "smoke::visibility::dummy::kinds::AsyncFunction" [label="pub(self) async fn|smoke::visibility::dummy::kinds::AsyncFunction", fillcolor="#db5367"]; // "async fn" node
+    "smoke::visibility::dummy::kinds::Struct" [label="pub(self) struct|smoke::visibility::dummy::kinds::Struct", fillcolor="#db5367"]; // "struct" node
+    "smoke::visibility::dummy::kinds::Trait" [label="pub(self) trait|smoke::visibility::dummy::kinds::Trait", fillcolor="#db5367"]; // "trait" node
+    "smoke::visibility::dummy::kinds::TraitAlias" [label="pub(self) type|smoke::visibility::dummy::kinds::TraitAlias", fillcolor="#db5367"]; // "type" node
+    "smoke::visibility::dummy::kinds::TypeAlias" [label="pub(self) type|smoke::visibility::dummy::kinds::TypeAlias", fillcolor="#db5367"]; // "type" node
+    "str" [label="external builtin|str", fillcolor="#81c169"]; // "builtin" node
+
+    "smoke::derives::Dummy::clone" -> "bool" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::derives::Dummy::clone" -> "smoke::derives::Dummy" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::functions::Crate" -> "smoke::target::Target" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::functions::Std" -> "alloc::string::String" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::functions::body" -> "alloc::string::String" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::functions::body" -> "i32" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::functions::body" -> "smoke::functions::Local" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::functions::body" -> "smoke::target::Target" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::functions::body" -> "str" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::functions::inputs" -> "alloc::string::String" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::functions::inputs" -> "i32" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::functions::inputs" -> "smoke::functions::Local" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::functions::inputs" -> "smoke::target::Target" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::functions::inputs" -> "str" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::functions::outputs" -> "alloc::string::String" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::functions::outputs" -> "i32" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::functions::outputs" -> "smoke::functions::Local" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::functions::outputs" -> "smoke::target::Target" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::functions::outputs" -> "str" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::methods::Crate" -> "smoke::target::Target" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::methods::Dummy::body" -> "alloc::string::String" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::methods::Dummy::body" -> "i32" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::methods::Dummy::body" -> "smoke::methods::Local" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::methods::Dummy::body" -> "smoke::target::Target" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::methods::Dummy::body" -> "str" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::methods::Dummy::inputs" -> "alloc::string::String" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::methods::Dummy::inputs" -> "i32" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::methods::Dummy::inputs" -> "smoke::methods::Local" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::methods::Dummy::inputs" -> "smoke::target::Target" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::methods::Dummy::inputs" -> "str" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::methods::Dummy::outputs" -> "alloc::string::String" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::methods::Dummy::outputs" -> "i32" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::methods::Dummy::outputs" -> "smoke::methods::Local" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::methods::Dummy::outputs" -> "smoke::target::Target" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::methods::Dummy::outputs" -> "str" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::methods::Std" -> "alloc::string::String" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::uses" -> "alloc::fmt" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::uses" -> "core::cmp" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::uses" -> "core::ops" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::uses" -> "smoke::hierarchy" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::uses::cycle::node_0" -> "smoke::uses::cycle::node_1" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::uses::cycle::node_1::node_2" -> "smoke::uses::cycle::node_0" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::visibility::dummy::kinds::AsyncFunction" -> "core::future::future::Future" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::visibility::dummy::kinds::AsyncFunction" -> "core::marker::Sized" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::visibility::dummy::kinds::TraitAlias" -> "smoke::visibility::dummy::kinds::Trait" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+    "smoke::visibility::dummy::kinds::TypeAlias" -> "smoke::visibility::dummy::kinds::Struct" [label="uses", color="#7f7f7f", style="dashed"] [constraint=false]; // "uses" edge
+
+}

tests/snapshots/general__help__smoke.snap

@@ -21,4 +21,4 @@ Commands:
 
 Options:
   -h, --help     Print help
-  -V, --version  Print version
+  -V, --version  Print version