Merge pull request #649 from apogeeoak/iterator3

Enabled iterators3.rs to run without commented out tests.

exercises/standard_library_types/iterators3.rs

@@ -1,11 +1,10 @@
 // iterators3.rs
 // This is a bigger exercise than most of the others! You can do it!
 // Here is your mission, should you choose to accept it:
-// 1. Complete the divide function to get the first four tests to pass
-// 2. Uncomment the last two tests and get them to pass by filling in
-//    values for `x` using `division_results`.
+// 1. Complete the divide function to get the first four tests to pass.
+// 2. Get the remaining tests to pass by completing the result_with_list and
+//    list_of_results functions.
 // Execute `rustlings hint iterators3` to get some hints!
-// Have fun :-)
 
 // I AM NOT DONE
 
@@ -21,16 +20,28 @@ pub struct NotDivisibleError {
     divisor: i32,
 }
 
-// This function should calculate `a` divided by `b` if `a` is
-// evenly divisible by b.
-// Otherwise, it should return a suitable error.
+// Calculate `a` divided by `b` if `a` is evenly divisible by `b`.
+// Otherwise, return a suitable error.
 pub fn divide(a: i32, b: i32) -> Result<i32, DivisionError> {}
 
+// Complete the function and return a value of the correct type so the test passes.
+// Desired output: Ok([1, 11, 1426, 3])
+fn result_with_list() -> () {
+    let numbers = vec![27, 297, 38502, 81];
+    let division_results = numbers.into_iter().map(|n| divide(n, 27));
+}
+
+// Complete the function and return a value of the correct type so the test passes.
+// Desired output: [Ok(1), Ok(11), Ok(1426), Ok(3)]
+fn list_of_results() -> () {
+    let numbers = vec![27, 297, 38502, 81];
+    let division_results = numbers.into_iter().map(|n| divide(n, 27));
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
 
-    // Tests that verify your `divide` function implementation
     #[test]
     fn test_success() {
         assert_eq!(divide(81, 9), Ok(9));
@@ -57,22 +68,16 @@ mod tests {
         assert_eq!(divide(0, 81), Ok(0));
     }
 
-    // Iterator exercises using your `divide` function
-    /*
     #[test]
-    fn result_with_list() {
-        let numbers = vec![27, 297, 38502, 81];
-        let division_results = numbers.into_iter().map(|n| divide(n, 27));
-        let x //... Fill in here!
-        assert_eq!(format!("{:?}", x), "Ok([1, 11, 1426, 3])");
+    fn test_result_with_list() {
+        assert_eq!(format!("{:?}", result_with_list()), "Ok([1, 11, 1426, 3])");
     }
 
     #[test]
-    fn list_of_results() {
-        let numbers = vec![27, 297, 38502, 81];
-        let division_results = numbers.into_iter().map(|n| divide(n, 27));
-        let x //... Fill in here!
-        assert_eq!(format!("{:?}", x), "[Ok(1), Ok(11), Ok(1426), Ok(3)]");
+    fn test_list_of_results() {
+        assert_eq!(
+            format!("{:?}", list_of_results()),
+            "[Ok(1), Ok(11), Ok(1426), Ok(3)]"
+        );
     }
-    */
 }

info.toml

@@ -725,11 +725,15 @@ name = "iterators3"
 path = "exercises/standard_library_types/iterators3.rs"
 mode = "test"
 hint = """
-Minor hint: In each of the two cases in the match in main, you can create x with either
-a 'turbofish' or by hinting the type of x to the compiler. You may try both.
+The divide function needs to return the correct error when even division is not
+possible.
 
-Major hint: Have a look at the Iter trait and at the explanation of its collect function.
-Especially the part about Result is interesting."""
+The division_results variable needs to be collected into a collection type.
+
+The result_with_list function needs to return a single Result where the success
+case is a vector of integers and the failure case is a DivisionError.
+
+The list_of_results function needs to return a vector of results."""
 
 [[exercises]]
 name = "iterators4"