More OPA conformance; in-progress: ability to trace interpreter (#63)

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>

src/builtins/deprecated.rs

@@ -73,6 +73,7 @@ fn cast_array(span: &Span, params: &[Ref<Expr>], args: &[Value], strict: bool) -
     ensure_args_count(span, name, params, args, 1)?;
     match &args[0] {
         Value::Array(_) => Ok(args[0].clone()),
+        Value::Set(s) => Ok(Value::from_array(s.iter().cloned().collect())),
         _ if strict => bail!(params[0].span().error("array required")),
         _ => Ok(Value::Undefined),
     }
@@ -113,6 +114,7 @@ fn cast_set(span: &Span, params: &[Ref<Expr>], args: &[Value], strict: bool) ->
     ensure_args_count(span, name, params, args, 1)?;
     match &args[0] {
         Value::Set(_) => Ok(args[0].clone()),
+        Value::Array(a) => Ok(Value::from_set(a.iter().cloned().collect())),
         _ if strict => bail!(params[0].span().error("set required")),
         _ => Ok(Value::Undefined),
     }

src/builtins/numbers.rs

@@ -18,6 +18,7 @@ pub fn register(m: &mut HashMap<&'static str, builtins::BuiltinFcn>) {
     m.insert("ceil", (ceil, 1));
     m.insert("floor", (floor, 1));
     m.insert("numbers.range", (range, 2));
+    m.insert("numbers.range_step", (range_step, 3));
     m.insert("rand.intn", (intn, 2));
     m.insert("round", (round, 1));
 }
@@ -29,6 +30,7 @@ pub fn arithmetic_operation(
     expr2: &Expr,
     v1: Value,
     v2: Value,
+    strict: bool,
 ) -> Result<Value> {
     let op_name = format!("{:?}", op).to_lowercase();
     let v1 = ensure_numeric(op_name.as_str(), expr1, &v1)?;
@@ -38,9 +40,11 @@ pub fn arithmetic_operation(
         ArithOp::Add => v1.add(&v2)?,
         ArithOp::Sub => v1.sub(&v2)?,
         ArithOp::Mul => v1.mul(&v2)?,
-        ArithOp::Div if v2 == Number::from(0u64) => bail!(span.error("divide by zero")),
+        ArithOp::Div if strict && v2 == Number::from(0u64) => bail!(span.error("divide by zero")),
+        ArithOp::Div if v2 == Number::from(0u64) => return Ok(Value::Undefined),
         ArithOp::Div => v1.divide(&v2)?,
-        ArithOp::Mod if v2 == Number::from(0u64) => bail!(span.error("modulo by zero")),
+        ArithOp::Mod if strict && v2 == Number::from(0u64) => bail!(span.error("modulo by zero")),
+        ArithOp::Mod if v2 == Number::from(0u64) => return Ok(Value::Undefined),
         ArithOp::Mod if !v1.is_integer() || !v2.is_integer() => {
             bail!(span.error("modulo on floating-point number"))
         }
@@ -69,25 +73,33 @@ fn floor(span: &Span, params: &[Ref<Expr>], args: &[Value], _strict: bool) -> Re
     ))
 }
 
-fn range(span: &Span, params: &[Ref<Expr>], args: &[Value], _strict: bool) -> Result<Value> {
-    ensure_args_count(span, "numbers.range", params, args, 2)?;
-    let v1 = ensure_numeric("numbers.range", &params[0], &args[0].clone())?;
-    let v2 = ensure_numeric("numbers.range", &params[1], &args[1].clone())?;
+fn range(span: &Span, params: &[Ref<Expr>], args: &[Value], strict: bool) -> Result<Value> {
+    let name = "numbers.range";
+    ensure_args_count(span, name, params, args, 2)?;
+    let v1 = ensure_numeric(name, &params[0], &args[0].clone())?;
+    let v2 = ensure_numeric(name, &params[1], &args[1].clone())?;
 
-    let (incr, num_elements) = match (v1.as_i64(), v2.as_i64()) {
-        (Some(v1), Some(v2)) if v2 > v1 => (1, v2 + 1 - v1),
-        (Some(v1), Some(v2)) => (-1, v1 + 1 - v2),
-        _ => {
-            // TODO: OPA returns undefined here.
-            // Can we emit a warning?
-            return Ok(Value::Undefined);
-        }
+    match v1.is_integer() {
+        false if strict => bail!(params[0].span().error("operand must be integer")),
+        false => return Ok(Value::Undefined),
+        _ => (),
+    }
+
+    match v2.is_integer() {
+        false if strict => bail!(params[1].span().error("operand must be integer")),
+        false => return Ok(Value::Undefined),
+        _ => (),
+    }
+
+    let (incr, num_elements) = match v2.sub(&v1)?.as_i64() {
+        Some(v) if v >= 0 => (1i64, v as usize + 1),
+        Some(v) => (-1i64, (-v + 1) as usize),
+        _ => bail!(span.error("could not determine number of elements")),
     };
 
-    let mut values = Vec::with_capacity(num_elements as usize);
-
+    let mut values = Vec::with_capacity(num_elements);
     let mut v = v1;
-    let incr = Number::from(incr as i64);
+    let incr = Number::from(incr);
     while v != v2 {
         values.push(Value::from(v.clone()));
         v.add_assign(&incr)?;
@@ -96,10 +108,51 @@ fn range(span: &Span, params: &[Ref<Expr>], args: &[Value], _strict: bool) -> Re
     Ok(Value::from_array(values))
 }
 
+fn range_step(span: &Span, params: &[Ref<Expr>], args: &[Value], strict: bool) -> Result<Value> {
+    let name = "numbers.range_step";
+    ensure_args_count(span, name, params, args, 3)?;
+    let v1 = ensure_numeric(name, &params[0], &args[0].clone())?;
+    let v2 = ensure_numeric(name, &params[1], &args[1].clone())?;
+    let incr = ensure_numeric(name, &params[2], &args[2].clone())?;
+
+    match v1.is_integer() {
+        false if strict => bail!(params[0].span().error("operand must be integer")),
+        false => return Ok(Value::Undefined),
+        _ => (),
+    }
+
+    match v2.is_integer() {
+        false if strict => bail!(params[1].span().error("operand must be integer")),
+        false => return Ok(Value::Undefined),
+        _ => (),
+    }
+
+    if strict && (!incr.is_integer() || incr <= Number::from(0u64)) {
+        bail!(params[2].span().error("step must be a positive integer"))
+    }
+
+    let (incr, num_elements) = match (v2.sub(&v1)?.as_i64(), incr.as_i64()) {
+        (Some(v), Some(incr)) if v >= 0 => (incr, v / incr + 1),
+        (Some(v), Some(incr)) => (-incr, -v / incr + 1),
+        _ => bail!(span.error("could not determine number of elements")),
+    };
+
+    let mut values = Vec::with_capacity(num_elements as usize);
+    let incr = Number::from(incr);
+    let mut v = v1;
+    while (v <= v2 && incr.is_positive()) || (v >= v2 && !incr.is_positive()) {
+        values.push(Value::from(v.clone()));
+        v.add_assign(&incr)?;
+    }
+
+    Ok(Value::from_array(values))
+}
+
 fn round(span: &Span, params: &[Ref<Expr>], args: &[Value], _strict: bool) -> Result<Value> {
-    ensure_args_count(span, "round", params, args, 1)?;
+    let name = "round";
+    ensure_args_count(span, name, params, args, 1)?;
     Ok(Value::from(
-        ensure_numeric("round", &params[0], &args[0])?.round(),
+        ensure_numeric(name, &params[0], &args[0])?.round(),
     ))
 }
 

src/builtins/semver.rs

@@ -35,9 +35,18 @@ fn compare(span: &Span, params: &[Ref<Expr>], args: &[Value], _strict: bool) ->
     Ok(Value::from(result as i64))
 }
 
-fn is_valid(span: &Span, params: &[Ref<Expr>], args: &[Value], _strict: bool) -> Result<Value> {
+fn is_valid(span: &Span, params: &[Ref<Expr>], args: &[Value], strict: bool) -> Result<Value> {
     let name = "semver.is_valid";
     ensure_args_count(span, name, params, args, 1)?;
-    let v = ensure_string(name, &params[0], &args[0])?;
-    Ok(Value::Bool(Version::parse(&v).is_ok()))
+    Ok(Value::Bool(
+        Version::parse(&if strict {
+            ensure_string(name, &params[0], &args[0])?
+        } else {
+            match &args[0] {
+                Value::String(s) => s.clone(),
+                _ => return Ok(Value::Bool(false)),
+            }
+        })
+        .is_ok(),
+    ))
 }

src/builtins/strings.rs

@@ -157,6 +157,41 @@ fn split(span: &Span, params: &[Ref<Expr>], args: &[Value], _strict: bool) -> Re
     ))
 }
 
+fn to_string(v: &Value, unescape: bool) -> String {
+    match v {
+        Value::Null => "null".to_owned(),
+        Value::Bool(b) => b.to_string(),
+        Value::String(s) if unescape => serde_json::to_string(&s).unwrap_or(s.as_ref().to_string()),
+        Value::String(s) => s.as_ref().to_string(),
+        Value::Number(n) => n.format_decimal(),
+        Value::Array(a) => {
+            "[".to_owned()
+                + &a.iter()
+                    .map(|e| to_string(e, true))
+                    .collect::<Vec<String>>()
+                    .join(", ")
+                + "]"
+        }
+        Value::Set(s) => {
+            "{".to_owned()
+                + &s.iter()
+                    .map(|e| to_string(e, true))
+                    .collect::<Vec<String>>()
+                    .join(", ")
+                + "}"
+        }
+        Value::Object(o) => {
+            "{".to_owned()
+                + &o.iter()
+                    .map(|(k, v)| to_string(k, true) + ": " + &to_string(v, true))
+                    .collect::<Vec<String>>()
+                    .join(", ")
+                + "}"
+        }
+        Value::Undefined => "#undefined".to_string(),
+    }
+}
+
 fn sprintf(span: &Span, params: &[Ref<Expr>], args: &[Value], _strict: bool) -> Result<Value> {
     let name = "sprintf";
     ensure_args_count(span, name, params, args, 2)?;
@@ -219,6 +254,9 @@ fn sprintf(span: &Span, params: &[Ref<Expr>], args: &[Value], _strict: bool) ->
         // Handle Golang printing verbs.
         // https://pkg.go.dev/fmt
         match (verb, arg) {
+            ('s', Value::String(sv)) => s += sv.as_ref(),
+            ('s', v) => s += &to_string(v, false),
+
             ('v', _) => s += format!("{arg}").as_str(),
             ('b', Value::Number(f)) if f.is_integer() => {
                 let (sign, v) = get_sign_value(f);
@@ -315,11 +353,6 @@ fn sprintf(span: &Span, params: &[Ref<Expr>], args: &[Value], _strict: bool) ->
                 bail!(args_span.error("floating-point number specified for format verb {verb}."));
             }
 
-            ('s', Value::String(sv)) => s += sv.as_ref(),
-            ('s', _) => {
-                bail!(args_span.error("invalid non string argument specified for format verb %s"));
-            }
-
             ('+', _) if chars.next() == Some('v') => {
                 bail!(args_span.error("Go-syntax fields names format verm %#v is not supported."));
             }