Addition of step in export_range

Author: StatisMike

godot-core/src/property.rs

@@ -153,22 +153,26 @@ pub mod export_info_functions {
     pub fn export_range(
         min: f64,
         max: f64,
+        step: Option<f64>,
         or_greater: bool,
         or_less: bool,
         exp: bool,
         radians: bool,
         degrees: bool,
         hide_slider: bool,
     ) -> PropertyHintInfo {
-        let min_max = format!("{},{}", min, max);
-
+        let hint_beginning = if let Some(step) = step {
+            format!("{min},{max},{step}")
+        } else {
+            format!("{min},{max}")
+        };
         let rest =
             comma_separate_boolean_idents!(or_greater, or_less, exp, radians, degrees, hide_slider);
 
         let hint_string = if rest.is_empty() {
-            min_max
+            hint_beginning
         } else {
-            format!("{min_max},{rest}")
+            format!("{hint_beginning},{rest}")
         };
 
         PropertyHintInfo {

godot-macros/src/class/data_models/field_export.rs

@@ -31,6 +31,7 @@ pub enum FieldExport {
     Range {
         min: TokenStream,
         max: TokenStream,
+        step: TokenStream,
         or_greater: bool,
         or_less: bool,
         exp: bool,
@@ -265,6 +266,15 @@ impl FieldExport {
 
         let min = parser.next_expr()?;
         let max = parser.next_expr()?;
+        // TODO: During parser refactor, try to remove the need for `is_next_ident` there. Currently needed only for this functionality.
+        // See discussion for rationale here: https://github.com/godot-rust/gdext/pull/484#pullrequestreview-1738612069
+        let step = match parser.is_next_ident() {
+            Some(false) => {
+                let value = parser.next_expr()?;
+                quote! { Some(#value) }
+            }
+            _ => quote! { None },
+        };
 
         let mut options = HashSet::new();
 
@@ -277,6 +287,7 @@ impl FieldExport {
         Ok(FieldExport::Range {
             min,
             max,
+            step,
             or_greater: options.contains("or_greater"),
             or_less: options.contains("or_less"),
             exp: options.contains("exp"),
@@ -360,14 +371,15 @@ impl FieldExport {
             FieldExport::Range {
                 min,
                 max,
+                step,
                 or_greater,
                 or_less,
                 exp,
                 radians,
                 degrees,
                 hide_slider,
             } => quote_export_func! {
-                export_range(#min, #max, #or_greater, #or_less, #exp, #radians, #degrees, #hide_slider)
+                export_range(#min, #max, #step, #or_greater, #or_less, #exp, #radians, #degrees, #hide_slider)
             },
 
             FieldExport::Enum { variants } => {

godot-macros/src/util/list_parser.rs

@@ -132,6 +132,19 @@ impl ListParser {
         Ok(Some(kv.ident()?))
     }
 
+    /// Check if the next element of the list is an identifier.
+    ///
+    /// Returns `None` if there are no more elements left, `Some(true)` if the next element is identifier and `Some(false)` if it is not.
+    pub fn is_next_ident(&mut self) -> Option<bool> {
+        let Some(kv) = self.peek() else {
+            return None;
+        };
+
+        let res = kv.as_ident();
+
+        Some(res.is_ok())
+    }
+
     /// Take the next element of the list, if it is an identifier.
     ///
     /// Returns `Ok(None)` if there are no more elements left or the next element isn't an identifier.

itest/rust/build.rs

@@ -424,8 +424,8 @@ fn generate_property_template(inputs: &[Input]) -> PropertyTests {
             export_multiline: GString,
             #[export(range = (0.0, 20.0))]
             export_range_float_0_20: f64,
-            // We're missing step currently.
-            //  #[export(range = (-10, 20 /*, 0.2 */))] export_range_float_neg_10_20_02: f64,
+            #[export(range = (-10.0, 20.0, 0.2))]
+            export_range_float_neg10_20_02: f64,
             // We can only export ranges of floats currently.
             //  #[export(range = (0, 100, 1, "or_greater", "or_less"))] export_range_int_0_100_1_or_greater_or_less: int,
             #[export(exp_easing)]
@@ -473,7 +473,7 @@ fn generate_property_template(inputs: &[Input]) -> PropertyTests {
 @export_global_dir var export_global_dir: String
 @export_multiline var export_multiline: String
 @export_range(0, 20) var export_range_float_0_20: float
-@export_range(-10, 20, 0.2) var export_range_float_neg_10_20_02: float
+@export_range(-10, 20, 0.2) var export_range_float_neg10_20_02: float
 @export_range(0, 100, 1, "or_greater", "or_less") var export_range_int_0_100_1_or_greater_or_less: int
 @export_exp_easing var export_exp_easing: float
 @export_color_no_alpha var export_color_no_alpha: Color

itest/rust/src/object_tests/property_test.rs

@@ -237,6 +237,9 @@ struct CheckAllExports {
     #[export(range = (0.0, 10.0, or_greater, or_less, exp, radians, hide_slider))]
     range_exported: f64,
 
+    #[export(range = (0.0, 10.0, 0.2, or_greater, or_less, exp, radians, hide_slider))]
+    range_exported_with_step: f64,
+
     #[export(enum = (A = 10, B, C, D = 20))]
     enum_exported: i64,