Merge pull request #26 from technocreatives/feature/arbitrary-floats

Generate arbitray floats

Author: Pascal Hertleif

src/includes/arbitrary_helpers.rs

@@ -0,0 +1,17 @@
+#[cfg(feature = "arb")]
+trait UnstructuredFloatExt {
+    fn float_in_range(&mut self, range: core::ops::RangeInclusive<f32>) -> arbitrary::Result<f32>;
+}
+
+#[cfg(feature = "arb")]
+impl UnstructuredFloatExt for arbitrary::Unstructured<'_> {
+    fn float_in_range(&mut self, range: core::ops::RangeInclusive<f32>) -> arbitrary::Result<f32> {
+        let min = range.start();
+        let max = range.end();
+        let steps = u32::MAX;
+        let factor = (max - min) / (steps as f32);
+        let random_int: u32 = self.int_in_range(0..=steps)?;
+        let random = min + factor * (random_int as f32);
+        Ok(random)
+    }
+}

src/lib.rs

@@ -58,6 +58,7 @@ pub fn codegen(dbc_name: &str, dbc_content: &[u8], out: impl Write, debug: bool)
     writeln!(&mut w, "fn main() {{}}")?;
     writeln!(&mut w)?;
     w.write_all(include_bytes!("./includes/errors.rs"))?;
+    w.write_all(include_bytes!("./includes/arbitrary_helpers.rs"))?;
     writeln!(&mut w)?;
 
     Ok(())
@@ -683,8 +684,11 @@ fn signal_to_arbitrary(signal: &Signal) -> String {
     if signal.signal_size == 1 {
         "u.int_in_range(0..=1)? == 1".to_string()
     } else if signal_is_float_in_rust(signal) {
-        // TODO generate arbitrary value for float
-        format!("{}_f32", signal.min())
+        format!(
+            "u.float_in_range({min}_f32..={max}_f32)?",
+            min = signal.min(),
+            max = signal.max()
+        )
     } else {
         format!(
             "u.int_in_range({min}..={max})?",

testing/can-messages/build.rs

@@ -8,6 +8,7 @@ fn main() -> Result<()> {
     let dbc_file = fs::read("../dbc-examples/example.dbc")?;
     let mut out = BufWriter::new(File::create("src/messages.rs")?);
     println!("cargo:rerun-if-changed=../dbc-examples/example.dbc");
+    println!("cargo:rerun-if-changed=../../src");
 
     dbc_codegen::codegen("example.dbc", &dbc_file, &mut out, true)?;
     Ok(())

testing/can-messages/src/messages.rs

@@ -175,8 +175,8 @@ impl core::convert::TryFrom<&[u8]> for Foo {
 #[cfg(feature = "arb")]
 impl<'a> Arbitrary<'a> for Foo {
     fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self, arbitrary::Error> {
-        let voltage = 0_f32;
-        let current = -2048_f32;
+        let voltage = u.float_in_range(0_f32..=63.9990234375_f32)?;
+        let current = u.float_in_range(-2048_f32..=2047.9375_f32)?;
         Foo::new(voltage, current).map_err(|_| arbitrary::Error::IncorrectFormat)
     }
 }
@@ -434,7 +434,7 @@ impl core::convert::TryFrom<&[u8]> for Bar {
 impl<'a> Arbitrary<'a> for Bar {
     fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self, arbitrary::Error> {
         let one = u.int_in_range(0..=3)?;
-        let two = 0_f32;
+        let two = u.float_in_range(0_f32..=100_f32)?;
         let three = u.int_in_range(0..=7)?;
         let four = u.int_in_range(0..=3)?;
         let xtype = u.int_in_range(0..=1)? == 1;
@@ -707,7 +707,7 @@ impl core::convert::TryFrom<&[u8]> for Amet {
 impl<'a> Arbitrary<'a> for Amet {
     fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self, arbitrary::Error> {
         let one = u.int_in_range(0..=3)?;
-        let two = 0_f32;
+        let two = u.float_in_range(0_f32..=100_f32)?;
         let three = u.int_in_range(0..=7)?;
         let four = u.int_in_range(0..=3)?;
         let five = u.int_in_range(0..=1)? == 1;
@@ -816,3 +816,20 @@ pub enum CanError {
     },
     InvalidPayloadSize,
 }
+#[cfg(feature = "arb")]
+trait UnstructuredFloatExt {
+    fn float_in_range(&mut self, range: core::ops::RangeInclusive<f32>) -> arbitrary::Result<f32>;
+}
+
+#[cfg(feature = "arb")]
+impl UnstructuredFloatExt for arbitrary::Unstructured<'_> {
+    fn float_in_range(&mut self, range: core::ops::RangeInclusive<f32>) -> arbitrary::Result<f32> {
+        let min = range.start();
+        let max = range.end();
+        let steps = u32::MAX;
+        let factor = (max - min) / (steps as f32);
+        let random_int: u32 = self.int_in_range(0..=steps)?;
+        let random = min + factor * (random_int as f32);
+        Ok(random)
+    }
+}