refactor(lint): prefer idiomatic for loops (#974)

Cargo.toml

@@ -61,6 +61,12 @@ rand_chacha = "0.3.1"
 rstest = "0.18.2"
 serde_json = "1.0.109"
 
+[lints.rust]
+unsafe_code = "forbid"
+[lints.clippy]
+explicit_iter_loop = "warn"
+needless_for_each = "warn"
+
 [features]
 #! The crate provides a set of optional features that can be enabled in your `cargo.toml` file.
 #!

src/layout/layout.rs

@@ -698,7 +698,7 @@ fn configure_variable_constraints(
     area: Element,
 ) -> Result<(), AddConstraintError> {
     // all variables are in the range [area.start, area.end]
-    for &variable in variables.iter() {
+    for &variable in variables {
         solver.add_constraint(variable | GE(REQUIRED) | area.start)?;
         solver.add_constraint(variable | LE(REQUIRED) | area.end)?;
     }
@@ -764,7 +764,7 @@ fn configure_flex_constraints(
     let spacing_f64 = f64::from(spacing) * FLOAT_PRECISION_MULTIPLIER;
     match flex {
         Flex::Legacy => {
-            for spacer in spacers_except_first_and_last.iter() {
+            for spacer in spacers_except_first_and_last {
                 solver.add_constraint(spacer.has_size(spacing_f64, SPACER_SIZE_EQ))?;
             }
             if let (Some(first), Some(last)) = (spacers.first(), spacers.last()) {
@@ -778,7 +778,7 @@ fn configure_flex_constraints(
             for (left, right) in spacers.iter().tuple_combinations() {
                 solver.add_constraint(left.has_size(right, SPACER_SIZE_EQ))?
             }
-            for spacer in spacers.iter() {
+            for spacer in spacers {
                 solver.add_constraint(spacer.has_min_size(spacing, SPACER_SIZE_EQ))?;
                 solver.add_constraint(spacer.has_size(area, SPACE_GROW))?;
             }
@@ -790,10 +790,10 @@ fn configure_flex_constraints(
             for (left, right) in spacers_except_first_and_last.iter().tuple_combinations() {
                 solver.add_constraint(left.has_size(right.size(), SPACER_SIZE_EQ))?
             }
-            for spacer in spacers_except_first_and_last.iter() {
+            for spacer in spacers_except_first_and_last {
                 solver.add_constraint(spacer.has_min_size(spacing, SPACER_SIZE_EQ))?;
             }
-            for spacer in spacers_except_first_and_last.iter() {
+            for spacer in spacers_except_first_and_last {
                 solver.add_constraint(spacer.has_size(area, SPACE_GROW))?;
             }
             if let (Some(first), Some(last)) = (spacers.first(), spacers.last()) {

src/lib.rs

@@ -1,5 +1,3 @@
-#![forbid(unsafe_code)]
-
 //! ![Demo](https://github.com/ratatui-org/ratatui/blob/1d39444e3dea6f309cf9035be2417ac711c1abc9/examples/demo2-destroy.gif?raw=true)
 //!
 //! <div align="center">

src/text/line.rs

@@ -470,7 +470,7 @@ impl WidgetRef for Line<'_> {
             None => 0,
         };
         let mut x = area.left().saturating_add(offset);
-        for span in self.spans.iter() {
+        for span in &self.spans {
             let span_width = span.width() as u16;
             let span_area = Rect {
                 x,

src/widgets/canvas/line.rs

@@ -128,7 +128,7 @@ mod tests {
         canvas.render(buffer.area, &mut buffer);
 
         let mut expected = Buffer::with_lines(expected_lines);
-        for cell in expected.content.iter_mut() {
+        for cell in &mut expected.content {
             if cell.symbol() == "•" {
                 cell.set_style(Style::new().red());
             }

src/widgets/chart.rs

@@ -1355,7 +1355,7 @@ mod tests {
 
         let expected = Buffer::with_lines(vec!["┌────┐", "│Data│", "└────┘"]);
 
-        [
+        for position in [
             LegendPosition::TopLeft,
             LegendPosition::Top,
             LegendPosition::TopRight,
@@ -1364,14 +1364,12 @@ mod tests {
             LegendPosition::Bottom,
             LegendPosition::BottomLeft,
             LegendPosition::BottomRight,
-        ]
-        .iter()
-        .for_each(|&position| {
+        ] {
             let chart = chart.clone().legend_position(Some(position));
             buffer.reset();
             chart.render(buffer.area, &mut buffer);
             assert_eq!(buffer, expected);
-        });
+        }
     }
 
     #[test]

src/widgets/table/table.rs

@@ -800,14 +800,14 @@ impl Table<'_> {
 }
 
 fn ensure_percentages_less_than_100(widths: &[Constraint]) {
-    widths.iter().for_each(|&w| {
+    for w in widths {
         if let Constraint::Percentage(p) = w {
             assert!(
-                p <= 100,
+                *p <= 100,
                 "Percentages should be between 0 and 100 inclusively."
-            )
+            );
         }
-    });
+    }
 }
 
 impl<'a> Styled for Table<'a> {