Stylistic: Prefer let-else

src/dumper.rs

@@ -167,7 +167,9 @@ fn yaml_emitter_dump_scalar(
     let plain_implicit = node.tag.as_deref() == Some(DEFAULT_SCALAR_TAG);
     let quoted_implicit = node.tag.as_deref() == Some(DEFAULT_SCALAR_TAG); // TODO: Why compare twice?! (even the C code does this)
 
-    if let NodeData::Scalar { value, style } = node.data {
+    let NodeData::Scalar { value, style } = node.data else {
+        unreachable!()
+    };
     let event = Event {
         data: EventData::Scalar {
             anchor,
@@ -180,9 +182,6 @@ fn yaml_emitter_dump_scalar(
         ..Default::default()
     };
     yaml_emitter_emit(emitter, event)
-    } else {
-        unreachable!()
-    }
 }
 
 fn yaml_emitter_dump_sequence(
@@ -193,7 +192,9 @@ fn yaml_emitter_dump_sequence(
 ) -> Result<(), EmitterError> {
     let implicit = node.tag.as_deref() == Some(DEFAULT_SEQUENCE_TAG);
 
-    if let NodeData::Sequence { items, style } = node.data {
+    let NodeData::Sequence { items, style } = node.data else {
+        unreachable!()
+    };
     let event = Event {
         data: EventData::SequenceStart {
             anchor,
@@ -213,9 +214,6 @@ fn yaml_emitter_dump_sequence(
         ..Default::default()
     };
     yaml_emitter_emit(emitter, event)
-    } else {
-        unreachable!()
-    }
 }
 
 fn yaml_emitter_dump_mapping(
@@ -226,7 +224,9 @@ fn yaml_emitter_dump_mapping(
 ) -> Result<(), EmitterError> {
     let implicit = node.tag.as_deref() == Some(DEFAULT_MAPPING_TAG);
 
-    if let NodeData::Mapping { pairs, style } = node.data {
+    let NodeData::Mapping { pairs, style } = node.data else {
+        unreachable!()
+    };
     let event = Event {
         data: EventData::MappingStart {
             anchor,
@@ -247,7 +247,4 @@ fn yaml_emitter_dump_mapping(
         ..Default::default()
     };
     yaml_emitter_emit(emitter, event)
-    } else {
-        unreachable!()
-    }
 }

src/emitter.rs

@@ -642,15 +642,13 @@ fn yaml_emitter_emit_sequence_start(
     yaml_emitter_process_anchor(emitter, anchor)?;
     yaml_emitter_process_tag(emitter, tag)?;
 
-    let style = if let EventData::SequenceStart { style, .. } = &event.data {
+    let EventData::SequenceStart { style, .. } = &event.data else {
-        *style
-    } else {
         unreachable!()
     };
 
     if emitter.flow_level != 0
         || emitter.canonical
-        || style == SequenceStyle::Flow
+        || *style == SequenceStyle::Flow
         || yaml_emitter_check_empty_sequence(emitter, event)
     {
         emitter.state = EmitterState::FlowSequenceFirstItem;
@@ -669,15 +667,13 @@ fn yaml_emitter_emit_mapping_start(
     yaml_emitter_process_anchor(emitter, anchor)?;
     yaml_emitter_process_tag(emitter, tag)?;
 
-    let style = if let EventData::MappingStart { style, .. } = &event.data {
+    let EventData::MappingStart { style, .. } = &event.data else {
-        *style
-    } else {
         unreachable!()
     };
 
     if emitter.flow_level != 0
         || emitter.canonical
-        || style == MappingStyle::Flow
+        || *style == MappingStyle::Flow
         || yaml_emitter_check_empty_mapping(emitter, event)
     {
         emitter.state = EmitterState::FlowMappingFirstKey;
@@ -759,20 +755,20 @@ fn yaml_emitter_select_scalar_style(
     scalar_analysis: &mut ScalarAnalysis,
     tag_analysis: &mut Option<TagAnalysis>,
 ) -> Result<(), EmitterError> {
-    if let EventData::Scalar {
+    let EventData::Scalar {
         plain_implicit,
         quoted_implicit,
         style,
         ..
     } = &event.data
-    {
+    else {
+        unreachable!()
+    };
+
     let mut style: ScalarStyle = *style;
     let no_tag = tag_analysis.is_none();
     if no_tag && !*plain_implicit && !*quoted_implicit {
-            yaml_emitter_set_emitter_error(
+        yaml_emitter_set_emitter_error(emitter, "neither tag nor implicit flags are specified")?;
-                emitter,
-                "neither tag nor implicit flags are specified",
-            )?;
     }
     if style == ScalarStyle::Any {
         style = ScalarStyle::Plain;
@@ -802,9 +798,7 @@ fn yaml_emitter_select_scalar_style(
         style = ScalarStyle::DoubleQuoted;
     }
     if (style == ScalarStyle::Literal || style == ScalarStyle::Folded)
-            && (!scalar_analysis.block_allowed
+        && (!scalar_analysis.block_allowed || emitter.flow_level != 0 || emitter.simple_key_context)
-                || emitter.flow_level != 0
-                || emitter.simple_key_context)
     {
         style = ScalarStyle::DoubleQuoted;
     }
@@ -816,9 +810,6 @@ fn yaml_emitter_select_scalar_style(
     }
     scalar_analysis.style = style;
     Ok(())
-    } else {
-        unreachable!()
-    }
 }
 
 fn yaml_emitter_process_anchor(

src/loader.rs

@@ -233,14 +233,12 @@ fn yaml_parser_load_alias(
     document: &mut Document,
     ctx: &[i32],
 ) -> Result<(), ComposerError> {
-    let anchor: &str = if let EventData::Alias { anchor } = &event.data {
+    let EventData::Alias { anchor } = &event.data else {
-        anchor
-    } else {
         unreachable!()
     };
 
     for alias_data in &parser.aliases {
-        if alias_data.anchor == anchor {
+        if alias_data.anchor == *anchor {
             return yaml_parser_load_node_add(document, ctx, alias_data.index);
         }
     }