Resolve remarks

Author: Gijsreyn

docs/reference/schemas/config/functions/skip.md

@@ -26,9 +26,9 @@ specified number of items from the start.
 - For strings: returns a new string containing characters after the specified index
 
 Both parameters are required. `originalValue` must be an array or a string.
-`numberToSkip` must be an integer greater than or equal to zero. If the number
-is greater than the length of the array or string, the function returns an
-empty array or an empty string respectively.
+`numberToSkip` must be an integer; negative values are treated as zero. If the
+number is greater than the length of the array or string, the function returns
+an empty array or an empty string respectively.
 
 ## Examples
 
@@ -112,7 +112,8 @@ Position: 1
 
 ### numberToSkip
 
-The number of items to skip from the start. Must be a non-negative integer.
+The number of items to skip from the start. Must be an integer. Negative values
+are treated as zero.
 
 ```yaml
 Type:     int
@@ -135,7 +136,6 @@ Type: array | string
 
 - `originalValue` is not an array or string
 - `numberToSkip` is not an integer
-- `numberToSkip` is negative
 
 ## Related functions
 

dsc/tests/dsc_functions.tests.ps1

@@ -412,10 +412,13 @@ Describe 'tests for function expressions' {
   It 'skip function works for: <expression>' -TestCases @(
     @{ expression = "[skip(createArray('a','b','c','d'), 2)]"; expected = @('c','d') }
     @{ expression = "[skip('hello', 2)]"; expected = 'llo' }
-    @{ expression = "[skip(createArray('a'), 0)]"; expected = @('a') }
-    @{ expression = "[skip('a', 0)]"; expected = 'a' }
+    @{ expression = "[skip(createArray('a','b'), 0)]"; expected = @('a','b') }
+    @{ expression = "[skip('abc', 0)]"; expected = 'abc' }
     @{ expression = "[skip(createArray('a','b'), 5)]"; expected = @() }
     @{ expression = "[skip('', 1)]"; expected = '' }
+    # Negative counts are treated as zero
+    @{ expression = "[skip(createArray('x','y'), -3)]"; expected = @('x','y') }
+    @{ expression = "[skip('xy', -1)]"; expected = 'xy' }
   ) {
     param($expression, $expected)
 

dsc_lib/locales/en-us.toml

@@ -409,7 +409,6 @@ invoked = "startsWith function"
 description = "Returns an array with all elements after the specified number, or a string with all characters after the specified number"
 invoked = "skip function"
 invalidNumberToSkip = "Second argument must be an integer"
-negativeNotAllowed = "Second argument cannot be negative"
 invalidOriginalValue = "First argument must be an array or string"
 
 [functions.string]

dsc_lib/src/functions/skip.rs

@@ -31,27 +31,28 @@ impl Function for Skip {
     fn invoke(&self, args: &[Value], _context: &Context) -> Result<Value, DscError> {
         debug!("{}", t!("functions.skip.invoked"));
 
-        let Some(count_i64) = args[1].as_i64() else {
-            return Err(DscError::Parser(t!("functions.skip.invalidNumberToSkip").to_string()));
-        };
-        if count_i64 < 0 {
-            return Err(DscError::Parser(t!("functions.skip.negativeNotAllowed").to_string()));
-        }
-        let count: usize = count_i64.try_into().unwrap_or(usize::MAX);
+        if let Some(count_i64) = args[1].as_i64() {
+            let count: usize = if count_i64 < 0 {
+                0
+            } else {
+                count_i64.try_into().unwrap_or(usize::MAX)
+            };
 
-        if let Some(array) = args[0].as_array() {
-            if count >= array.len() { return Ok(Value::Array(vec![])); }
-            let skipped = array.iter().skip(count).cloned().collect::<Vec<Value>>();
-            return Ok(Value::Array(skipped));
-        }
+            if let Some(array) = args[0].as_array() {
+                if count >= array.len() { return Ok(Value::Array(vec![])); }
+                let skipped = array.iter().skip(count).cloned().collect::<Vec<Value>>();
+                return Ok(Value::Array(skipped));
+            }
 
-        if let Some(s) = args[0].as_str() {
+            if let Some(s) = args[0].as_str() {
+                let result: String = s.chars().skip(count).collect();
+                return Ok(Value::String(result));
+            }
 
-            let result: String = s.chars().skip(count).collect();
-            return Ok(Value::String(result));
+            return Err(DscError::Parser(t!("functions.skip.invalidOriginalValue").to_string()));
         }
 
-        Err(DscError::Parser(t!("functions.skip.invalidOriginalValue").to_string()))
+        Err(DscError::Parser(t!("functions.skip.invalidNumberToSkip").to_string()))
     }
 }
 
@@ -81,4 +82,22 @@ mod tests {
         let result = parser.parse_and_execute("[skip(createArray('a','b'), 5)]", &Context::new()).unwrap();
         assert_eq!(result, Value::Array(vec![]));
     }
+
+    #[test]
+    fn skip_array_negative_is_zero() {
+        let mut parser = Statement::new().unwrap();
+        let result = parser.parse_and_execute("[skip(createArray('a','b','c'), -1)]", &Context::new()).unwrap();
+        assert_eq!(result, Value::Array(vec![
+            Value::String("a".into()),
+            Value::String("b".into()),
+            Value::String("c".into()),
+        ]));
+    }
+
+    #[test]
+    fn skip_string_negative_is_zero() {
+        let mut parser = Statement::new().unwrap();
+        let result = parser.parse_and_execute("[skip('ab', -2)]", &Context::new()).unwrap();
+        assert_eq!(result, Value::String("ab".into()));
+    }
 }