Merge branch 'feat/math-time-duration' of https://github.com/fchikwek…

…we/opentelemetry-collector-contrib into feat/math-time-duration

pkg/ottl/README.md

@@ -172,8 +172,8 @@ When defining an OTTL function, if the function needs to take an Enum then the f
 
 Math Expressions represent arithmetic calculations.  They support `+`, `-`, `*`, and `/`, along with `()` for grouping.
 
-Math Expressions currently support `int64` and`float64`. 
-Math Expressions also support `time.Time` and `time.Duration`, but only with `+` and `-` and only using the following rules: 
+Math Expressions currently support `int64`, `float64`, `time.Time` and `time.Duration`. 
+For `time.Time` and `time.Duration`, only `+` and `-` are supported with the following rules: 
   - A `time.Time` `-` a `time.Time` yields a `time.Duration`.
   - A `time.Duration` `+` a `time.Time` yields a `time.Time`. 
   - A `time.Time` `-`  a `time.Duration` yields a `time.Time`.

pkg/ottl/math.go

@@ -130,7 +130,7 @@ func performOpTime(x time.Time, y any, op mathOp) (any, error) {
 			result := x.Add(-1 * newY)
 			return result, nil
 		default:
-			return nil, fmt.Errorf("time.Time must be subtracted from time.Time or time.Duration; found %v instead", y)
+			return nil, fmt.Errorf("time.Time or time.Duration must be subtracted from time.Time; found %v instead", y)
 		}
 	}
 	return nil, fmt.Errorf("only addition and subtraction supported for time.Time and time.Duration")