From 9788fb4861abe563b31e1c73048682dab717d55a Mon Sep 17 00:00:00 2001
From: Noah Baldwin <noahwbaldwin@gmail.com>
Date: Sun, 12 Jan 2025 12:18:01 +1100
Subject: [PATCH] feat(oxvg_optimiser): #39 remove unused ns

---
 crates/oxvg_optimiser/src/jobs/mod.rs         |   1 +
 .../src/jobs/remove_unused_n_s.rs             | 201 ++++++++++++++++++
 ...emove_unused_n_s__remove_unused_n_s-2.snap |   9 +
 ...emove_unused_n_s__remove_unused_n_s-3.snap |  11 +
 ...emove_unused_n_s__remove_unused_n_s-4.snap |  11 +
 ...emove_unused_n_s__remove_unused_n_s-5.snap |  11 +
 ...emove_unused_n_s__remove_unused_n_s-6.snap |  11 +
 ...emove_unused_n_s__remove_unused_n_s-7.snap |   7 +
 ..._remove_unused_n_s__remove_unused_n_s.snap |   9 +
 9 files changed, 271 insertions(+)
 create mode 100644 crates/oxvg_optimiser/src/jobs/remove_unused_n_s.rs
 create mode 100644 crates/oxvg_optimiser/src/jobs/snapshots/oxvg_optimiser__jobs__remove_unused_n_s__remove_unused_n_s-2.snap
 create mode 100644 crates/oxvg_optimiser/src/jobs/snapshots/oxvg_optimiser__jobs__remove_unused_n_s__remove_unused_n_s-3.snap
 create mode 100644 crates/oxvg_optimiser/src/jobs/snapshots/oxvg_optimiser__jobs__remove_unused_n_s__remove_unused_n_s-4.snap
 create mode 100644 crates/oxvg_optimiser/src/jobs/snapshots/oxvg_optimiser__jobs__remove_unused_n_s__remove_unused_n_s-5.snap
 create mode 100644 crates/oxvg_optimiser/src/jobs/snapshots/oxvg_optimiser__jobs__remove_unused_n_s__remove_unused_n_s-6.snap
 create mode 100644 crates/oxvg_optimiser/src/jobs/snapshots/oxvg_optimiser__jobs__remove_unused_n_s__remove_unused_n_s-7.snap
 create mode 100644 crates/oxvg_optimiser/src/jobs/snapshots/oxvg_optimiser__jobs__remove_unused_n_s__remove_unused_n_s.snap

diff --git a/crates/oxvg_optimiser/src/jobs/mod.rs b/crates/oxvg_optimiser/src/jobs/mod.rs
index 27c7585..24060f0 100644
--- a/crates/oxvg_optimiser/src/jobs/mod.rs
+++ b/crates/oxvg_optimiser/src/jobs/mod.rs
@@ -86,6 +86,7 @@ jobs! {
     convert_transform: ConvertTransform (is_default: true),
     remove_empty_attrs: RemoveEmptyAttrs (is_default: true),
     remove_empty_containers: RemoveEmptyContainers (is_default: true),
+    remove_unused_n_s: RemoveUnusedNS (is_default: true),
     merge_paths: MergePaths (is_default: true),
     sort_attrs: SortAttrs (is_default: true),
     sort_defs_children: SortDefsChildren (is_default: true),
diff --git a/crates/oxvg_optimiser/src/jobs/remove_unused_n_s.rs b/crates/oxvg_optimiser/src/jobs/remove_unused_n_s.rs
new file mode 100644
index 0000000..359b8da
--- /dev/null
+++ b/crates/oxvg_optimiser/src/jobs/remove_unused_n_s.rs
@@ -0,0 +1,201 @@
+use std::collections::HashSet;
+
+use oxvg_ast::{
+    attribute::{Attr, Attributes},
+    element::Element,
+    visitor::{Context, PrepareOutcome, Visitor},
+};
+use serde::Deserialize;
+
+#[derive(Clone)]
+pub struct RemoveUnusedNS {
+    enabled: bool,
+    unused_namespaces: HashSet<String>,
+}
+
+impl<E: Element> Visitor<E> for RemoveUnusedNS {
+    type Error = String;
+
+    fn prepare(
+        &mut self,
+        _document: &E,
+        _context_flags: &mut oxvg_ast::visitor::ContextFlags,
+    ) -> oxvg_ast::visitor::PrepareOutcome {
+        if self.enabled {
+            PrepareOutcome::none
+        } else {
+            PrepareOutcome::skip
+        }
+    }
+
+    fn document(&mut self, document: &mut E) -> Result<(), Self::Error> {
+        document.for_each_element_child(|e| {
+            self.root_element(&e);
+        });
+        Ok(())
+    }
+
+    fn exit_document(
+        &mut self,
+        document: &mut E,
+        _context: &Context<E>,
+    ) -> Result<(), Self::Error> {
+        document.for_each_element_child(|e| {
+            self.exit_root_element(&e);
+        });
+        Ok(())
+    }
+}
+
+impl RemoveUnusedNS {
+    fn root_element<E: Element>(&mut self, element: &E) {
+        if element.prefix().is_none() && element.local_name().as_ref() == "svg" {
+            for attr in element.attributes().iter() {
+                if attr.prefix().is_some_and(|p| p.as_ref() == "xmlns") {
+                    self.unused_namespaces.insert(attr.local_name().to_string());
+                }
+            }
+        }
+        if self.unused_namespaces.is_empty() {
+            return;
+        }
+        let Some(prefix) = element.prefix().as_ref().map(ToString::to_string) else {
+            return;
+        };
+
+        self.unused_namespaces.remove(&prefix);
+        for attr in element.attributes().iter() {
+            if let Some(prefix) = attr.prefix().as_ref().map(ToString::to_string) {
+                self.unused_namespaces.remove(&prefix);
+            }
+        }
+    }
+
+    fn exit_root_element<E: Element>(&self, element: &E) {
+        if element.prefix().is_some() || element.local_name().as_ref() != "svg" {
+            return;
+        }
+
+        for name in &self.unused_namespaces {
+            log::debug!("removing xmlns:{name}");
+            element.remove_attribute(&format!("xmlns:{name}").into());
+        }
+    }
+}
+
+impl Default for RemoveUnusedNS {
+    fn default() -> Self {
+        Self {
+            enabled: true,
+            unused_namespaces: HashSet::new(),
+        }
+    }
+}
+
+impl<'de> Deserialize<'de> for RemoveUnusedNS {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: serde::Deserializer<'de>,
+    {
+        let enabled = bool::deserialize(deserializer)?;
+        Ok(Self {
+            enabled,
+            unused_namespaces: HashSet::new(),
+        })
+    }
+}
+
+#[test]
+fn remove_unused_n_s() -> anyhow::Result<()> {
+    use crate::test_config;
+
+    insta::assert_snapshot!(test_config(
+        r#"{ "removeUnusedNS": true }"#,
+        Some(
+            r#"<svg xmlns="http://www.w3.org/2000/svg" xmlns:test="http://trololololololololololo.com/">
+    <g>
+        test
+    </g>
+</svg>"#
+        ),
+    )?);
+
+    // FIXME: rcdom removes used xmlns
+    insta::assert_snapshot!(test_config(
+        r#"{ "removeUnusedNS": true }"#,
+        Some(
+            r#"<svg xmlns="http://www.w3.org/2000/svg" xmlns:test="http://trololololololololololo.com/">
+    <g test:attr="val">
+        test
+    </g>
+</svg>"#
+        ),
+    )?);
+
+    // FIXME: rcdom removes used xmlns
+    insta::assert_snapshot!(test_config(
+        r#"{ "removeUnusedNS": true }"#,
+        Some(
+            r#"<svg xmlns="http://www.w3.org/2000/svg" xmlns:test="http://trololololololololololo.com/" xmlns:test2="http://trololololololololololo.com/">
+    <g test:attr="val">
+        <g>
+            test
+        </g>
+    </g>
+</svg>"#
+        ),
+    )?);
+
+    // FIXME: rcdom removes used xmlns
+    insta::assert_snapshot!(test_config(
+        r#"{ "removeUnusedNS": true }"#,
+        Some(
+            r#"<svg xmlns="http://www.w3.org/2000/svg" xmlns:test="http://trololololololololololo.com/" xmlns:test2="http://trololololololololololo.com/">
+    <g test:attr="val">
+        <g test2:attr="val">
+            test
+        </g>
+    </g>
+</svg>"#
+        ),
+    )?);
+
+    // FIXME: rcdom removes used xmlns
+    insta::assert_snapshot!(test_config(
+        r#"{ "removeUnusedNS": true }"#,
+        Some(
+            r#"<svg xmlns="http://www.w3.org/2000/svg" xmlns:test="http://trololololololololololo.com/" xmlns:test2="http://trololololololololololo.com/">
+    <g>
+        <test:elem>
+            test
+        </test:elem>
+    </g>
+</svg>"#
+        ),
+    )?);
+
+    // FIXME: rcdom removes used xmlns
+    insta::assert_snapshot!(test_config(
+        r#"{ "removeUnusedNS": true }"#,
+        Some(
+            r#"<svg xmlns="http://www.w3.org/2000/svg" xmlns:test="http://trololololololololololo.com/" xmlns:test2="http://trololololololololololo.com/">
+    <test:elem>
+        <test2:elem>
+            test
+        </test2:elem>
+    </test:elem>
+</svg>"#
+        ),
+    )?);
+
+    insta::assert_snapshot!(test_config(
+        r#"{ "removeUnusedNS": true }"#,
+        Some(
+            r#"<svg xmlns="http://www.w3.org/2000/svg" inkscape:version="0.92.2 (5c3e80d, 2017-08-06)" sodipodi:docname="test.svg" xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape" xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd">
+    test
+</svg>"#
+        ),
+    )?);
+
+    Ok(())
+}
diff --git a/crates/oxvg_optimiser/src/jobs/snapshots/oxvg_optimiser__jobs__remove_unused_n_s__remove_unused_n_s-2.snap b/crates/oxvg_optimiser/src/jobs/snapshots/oxvg_optimiser__jobs__remove_unused_n_s__remove_unused_n_s-2.snap
new file mode 100644
index 0000000..de58e31
--- /dev/null
+++ b/crates/oxvg_optimiser/src/jobs/snapshots/oxvg_optimiser__jobs__remove_unused_n_s__remove_unused_n_s-2.snap
@@ -0,0 +1,9 @@
+---
+source: crates/oxvg_optimiser/src/jobs/remove_unused_n_s.rs
+expression: "test_config(r#\"{ \"removeUnusedNS\": true }\"#,\nSome(r#\"<svg xmlns=\"http://www.w3.org/2000/svg\" xmlns:test=\"http://trololololololololololo.com/\">\n    <g test:attr=\"val\">\n        test\n    </g>\n</svg>\"#),)?"
+---
+<svg xmlns="http://www.w3.org/2000/svg">
+    <g test:attr="val">
+        test
+    </g>
+</svg>
diff --git a/crates/oxvg_optimiser/src/jobs/snapshots/oxvg_optimiser__jobs__remove_unused_n_s__remove_unused_n_s-3.snap b/crates/oxvg_optimiser/src/jobs/snapshots/oxvg_optimiser__jobs__remove_unused_n_s__remove_unused_n_s-3.snap
new file mode 100644
index 0000000..b5e0a8a
--- /dev/null
+++ b/crates/oxvg_optimiser/src/jobs/snapshots/oxvg_optimiser__jobs__remove_unused_n_s__remove_unused_n_s-3.snap
@@ -0,0 +1,11 @@
+---
+source: crates/oxvg_optimiser/src/jobs/remove_unused_n_s.rs
+expression: "test_config(r#\"{ \"removeUnusedNS\": true }\"#,\nSome(r#\"<svg xmlns=\"http://www.w3.org/2000/svg\" xmlns:test=\"http://trololololololololololo.com/\" xmlns:test2=\"http://trololololololololololo.com/\">\n    <g test:attr=\"val\">\n        <g>\n            test\n        </g>\n    </g>\n</svg>\"#),)?"
+---
+<svg xmlns="http://www.w3.org/2000/svg">
+    <g test:attr="val">
+        <g>
+            test
+        </g>
+    </g>
+</svg>
diff --git a/crates/oxvg_optimiser/src/jobs/snapshots/oxvg_optimiser__jobs__remove_unused_n_s__remove_unused_n_s-4.snap b/crates/oxvg_optimiser/src/jobs/snapshots/oxvg_optimiser__jobs__remove_unused_n_s__remove_unused_n_s-4.snap
new file mode 100644
index 0000000..66cd99d
--- /dev/null
+++ b/crates/oxvg_optimiser/src/jobs/snapshots/oxvg_optimiser__jobs__remove_unused_n_s__remove_unused_n_s-4.snap
@@ -0,0 +1,11 @@
+---
+source: crates/oxvg_optimiser/src/jobs/remove_unused_n_s.rs
+expression: "test_config(r#\"{ \"removeUnusedNS\": true }\"#,\nSome(r#\"<svg xmlns=\"http://www.w3.org/2000/svg\" xmlns:test=\"http://trololololololololololo.com/\" xmlns:test2=\"http://trololololololololololo.com/\">\n    <g test:attr=\"val\">\n        <g test2:attr=\"val\">\n            test\n        </g>\n    </g>\n</svg>\"#),)?"
+---
+<svg xmlns="http://www.w3.org/2000/svg">
+    <g test:attr="val">
+        <g test2:attr="val">
+            test
+        </g>
+    </g>
+</svg>
diff --git a/crates/oxvg_optimiser/src/jobs/snapshots/oxvg_optimiser__jobs__remove_unused_n_s__remove_unused_n_s-5.snap b/crates/oxvg_optimiser/src/jobs/snapshots/oxvg_optimiser__jobs__remove_unused_n_s__remove_unused_n_s-5.snap
new file mode 100644
index 0000000..a6fcb19
--- /dev/null
+++ b/crates/oxvg_optimiser/src/jobs/snapshots/oxvg_optimiser__jobs__remove_unused_n_s__remove_unused_n_s-5.snap
@@ -0,0 +1,11 @@
+---
+source: crates/oxvg_optimiser/src/jobs/remove_unused_n_s.rs
+expression: "test_config(r#\"{ \"removeUnusedNS\": true }\"#,\nSome(r#\"<svg xmlns=\"http://www.w3.org/2000/svg\" xmlns:test=\"http://trololololololololololo.com/\" xmlns:test2=\"http://trololololololololololo.com/\">\n    <g>\n        <test:elem>\n            test\n        </test:elem>\n    </g>\n</svg>\"#),)?"
+---
+<svg xmlns="http://www.w3.org/2000/svg">
+    <g>
+        <test:elem xmlns:test="http://trololololololololololo.com/">
+            test
+        </test:elem>
+    </g>
+</svg>
diff --git a/crates/oxvg_optimiser/src/jobs/snapshots/oxvg_optimiser__jobs__remove_unused_n_s__remove_unused_n_s-6.snap b/crates/oxvg_optimiser/src/jobs/snapshots/oxvg_optimiser__jobs__remove_unused_n_s__remove_unused_n_s-6.snap
new file mode 100644
index 0000000..a889a48
--- /dev/null
+++ b/crates/oxvg_optimiser/src/jobs/snapshots/oxvg_optimiser__jobs__remove_unused_n_s__remove_unused_n_s-6.snap
@@ -0,0 +1,11 @@
+---
+source: crates/oxvg_optimiser/src/jobs/remove_unused_n_s.rs
+expression: "test_config(r#\"{ \"removeUnusedNS\": true }\"#,\nSome(r#\"<svg xmlns=\"http://www.w3.org/2000/svg\" xmlns:test=\"http://trololololololololololo.com/\" xmlns:test2=\"http://trololololololololololo.com/\">\n    <test:elem>\n        <test2:elem>\n            test\n        </test2:elem>\n    </test:elem>\n</svg>\"#),)?"
+---
+<svg xmlns="http://www.w3.org/2000/svg">
+    <test:elem xmlns:test="http://trololololololololololo.com/">
+        <test2:elem xmlns:test2="http://trololololololololololo.com/">
+            test
+        </test2:elem>
+    </test:elem>
+</svg>
diff --git a/crates/oxvg_optimiser/src/jobs/snapshots/oxvg_optimiser__jobs__remove_unused_n_s__remove_unused_n_s-7.snap b/crates/oxvg_optimiser/src/jobs/snapshots/oxvg_optimiser__jobs__remove_unused_n_s__remove_unused_n_s-7.snap
new file mode 100644
index 0000000..dfbbe8a
--- /dev/null
+++ b/crates/oxvg_optimiser/src/jobs/snapshots/oxvg_optimiser__jobs__remove_unused_n_s__remove_unused_n_s-7.snap
@@ -0,0 +1,7 @@
+---
+source: crates/oxvg_optimiser/src/jobs/remove_unused_n_s.rs
+expression: "test_config(r#\"{ \"removeUnusedNS\": true }\"#,\nSome(r#\"<svg xmlns=\"http://www.w3.org/2000/svg\" inkscape:version=\"0.92.2 (5c3e80d, 2017-08-06)\" sodipodi:docname=\"test.svg\" xmlns:inkscape=\"http://www.inkscape.org/namespaces/inkscape\" xmlns:sodipodi=\"http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd\">\n    test\n</svg>\"#),)?"
+---
+<svg xmlns="http://www.w3.org/2000/svg" inkscape:version="0.92.2 (5c3e80d, 2017-08-06)" sodipodi:docname="test.svg">
+    test
+</svg>
diff --git a/crates/oxvg_optimiser/src/jobs/snapshots/oxvg_optimiser__jobs__remove_unused_n_s__remove_unused_n_s.snap b/crates/oxvg_optimiser/src/jobs/snapshots/oxvg_optimiser__jobs__remove_unused_n_s__remove_unused_n_s.snap
new file mode 100644
index 0000000..d06a3fc
--- /dev/null
+++ b/crates/oxvg_optimiser/src/jobs/snapshots/oxvg_optimiser__jobs__remove_unused_n_s__remove_unused_n_s.snap
@@ -0,0 +1,9 @@
+---
+source: crates/oxvg_optimiser/src/jobs/remove_unused_n_s.rs
+expression: "test_config(r#\"{ \"removeUnusedNS\": true }\"#,\nSome(r#\"<svg xmlns=\"http://www.w3.org/2000/svg\" xmlns:test=\"http://trololololololololololo.com/\">\n    <g>\n        test\n    </g>\n</svg>\"#),)?"
+---
+<svg xmlns="http://www.w3.org/2000/svg">
+    <g>
+        test
+    </g>
+</svg>