[librsvg: 9/10] filter: simplify parsing

[Federico Mena Quintero <federico src gnome org>]

commit 6f4fe38e9eeb109bffda69cc38e930473af83044
Author: Paolo Borelli <pborelli gnome org>
Date:   Sat Dec 12 19:18:34 2020 +0100

    filter: simplify parsing
    
    Do not use IRI since None is not allowed. Also add a TODO to
    clarify why we have a FilterValue wrapper type with a single
    variant for now.

 src/drawing_ctx.rs |  4 ++--
 src/filter.rs      | 36 ++++++++++++++++++------------------
 2 files changed, 20 insertions(+), 20 deletions(-)
---
diff --git a/src/drawing_ctx.rs b/src/drawing_ctx.rs
index 40481bca..b471fc7e 100644
--- a/src/drawing_ctx.rs
+++ b/src/drawing_ctx.rs
@@ -860,10 +860,10 @@ impl DrawingCtx {
                         .try_fold(
                             child_surface,
                             |surface, filter| -> Result<_, RenderingError> {
-                                let FilterValue::URL(filter_uri) = filter;
+                                let FilterValue::Url(f) = filter;
                                 self.run_filter(
                                     acquired_nodes,
-                                    &filter_uri,
+                                    &f,
                                     node,
                                     values,
                                     surface,
diff --git a/src/filter.rs b/src/filter.rs
index a6f4fc8c..ffa7d5a3 100644
--- a/src/filter.rs
+++ b/src/filter.rs
@@ -10,7 +10,6 @@ use crate::document::{AcquiredNodes, NodeId};
 use crate::drawing_ctx::ViewParams;
 use crate::element::{Draw, Element, ElementResult, SetAttributes};
 use crate::error::ValueErrorKind;
-use crate::iri::IRI;
 use crate::length::*;
 use crate::node::{Node, NodeBorrow};
 use crate::parsers::{Parse, ParseValue};
@@ -151,8 +150,10 @@ impl Draw for Filter {}
 
 #[derive(Debug, Clone, PartialEq)]
 pub enum FilterValue {
-    URL(NodeId),
+    Url(NodeId),
+    // TODO: add functions from https://www.w3.org/TR/filter-effects-1/#filter-functions
 }
+
 #[derive(Debug, Clone, PartialEq)]
 pub struct FilterValueList(Vec<FilterValue>);
 
@@ -178,8 +179,11 @@ impl FilterValueList {
             return false;
         }
 
-        self.iter().all(|filter| match filter {
-            FilterValue::URL(filter_uri) => match acquired_nodes.acquire(filter_uri) {
+        self.iter()
+            .map(|v| match v {
+                FilterValue::Url(v) => v,
+            })
+            .all(|v| match acquired_nodes.acquire(v) {
                 Ok(acquired) => {
                     let filter_node = acquired.get();
 
@@ -189,7 +193,7 @@ impl FilterValueList {
                             rsvg_log!(
                                 "element {} will not be filtered since \"{}\" is not a filter",
                                 node,
-                                filter_uri,
+                                v,
                             );
                             false
                         }
@@ -199,12 +203,11 @@ impl FilterValueList {
                     rsvg_log!(
                         "element {} will not be filtered since its filter \"{}\" was not found",
                         node,
-                        filter_uri,
+                        v,
                     );
                     false
                 }
-            },
-        })
+            })
     }
 }
 
@@ -213,15 +216,12 @@ impl Parse for FilterValueList {
         let mut result = FilterValueList::default();
 
         loop {
-            let state = parser.state();
-
-            if let Ok(IRI::Resource(uri)) = parser.try_parse(|p| IRI::parse(p)) {
-                result.0.push(FilterValue::URL(uri));
-            } else {
-                parser.reset(&state);
-                let token = parser.next()?.clone();
-                return Err(parser.new_basic_unexpected_token_error(token).into());
-            }
+            let loc = parser.current_source_location();
+
+            let url = parser.expect_url()?;
+            let node_id =
+                NodeId::parse(&url).map_err(|e| loc.new_custom_error(ValueErrorKind::from(e)))?;
+            result.0.push(FilterValue::Url(node_id));
 
             if parser.is_exhausted() {
                 break;
@@ -242,7 +242,7 @@ mod tests {
         let n2 = NodeId::External("test.svg".to_string(), "baz".to_string());
         assert_eq!(
             FilterValueList::parse_str("url(foo.svg#bar) url(test.svg#baz)").unwrap(),
-            FilterValueList(vec![FilterValue::URL(n1), FilterValue::URL(n2)])
+            FilterValueList(vec![FilterValue::Url(n1), FilterValue::Url(n2)])
         );
     }