Wrap comment at 80 chars in 102.

Some of the inline comments in 102 are wrapped into very short lines. This
rewraps the shortest ones for readability.

exercises/102_testing.zig

@@ -37,63 +37,48 @@
 const std = @import("std");
 const testing = std.testing;
 
-// This is a simple function
+// This is a simple function that builds a sum from the passed parameters and
-// that builds a sum from the
+// returns.
-// passed parameters and returns.
 fn add(a: f16, b: f16) f16 {
     return a + b;
 }
 
-// The associated test.
+// The associated test. It always starts with the keyword "test", followed by a
-// It always starts with the keyword "test",
+// description of the tasks of the test. This is followed by the test cases in
-// followed by a description of the tasks
+// curly brackets.
-// of the test. This is followed by the
-// test cases in curly brackets.
 test "add" {
 
-    // The first test checks if the sum
+    // The first test checks if the sum of '41' and '1' gives '42', which is
-    // of '41' and '1' gives '42', which
+    // correct.
-    // is correct.
     try testing.expect(add(41, 1) == 42);
 
-    // Another way to perform this test
+    // Another way to perform this test is as follows:
-    // is as follows:
     try testing.expectEqual(42, add(41, 1));
 
-    // This time a test with the addition
+    // This time a test with the addition of a negative number:
-    // of a negative number:
     try testing.expect(add(5, -4) == 1);
 
     // And a floating point operation:
     try testing.expect(add(1.5, 1.5) == 3);
 }
 
-// Another simple function
+// Another simple function that returns the result of subtracting the two
-// that returns the result
-// of subtracting the two
 // parameters.
 fn sub(a: f16, b: f16) f16 {
     return a - b;
 }
 
-// The corresponding test
+// The corresponding test is not much different from the previous one. Except
-// is not much different
+// that it contains an error that you need to correct.
-// from the previous one.
-// Except that it contains
-// an error that you need
-// to correct.
 test "sub" {
     try testing.expect(sub(10, 5) == 6);
 
     try testing.expect(sub(3, 1.5) == 1.5);
 }
 
-// This function divides the
+// This function divides the numerator by the denominator. Here it is important
-// numerator by the denominator.
+// that the denominator must not be zero. This is checked and if it occurs an
-// Here it is important that the
+// error is returned.
-// denominator must not be zero.
-// This is checked and if it
-// occurs an error is returned.
 fn divide(a: f16, b: f16) !f16 {
     if (b == 0) return error.DivisionByZero;
     return a / b;
@@ -105,8 +90,7 @@ test "divide" {
     try testing.expect(divide(10, 2) catch unreachable == 5);
     try testing.expect(divide(1, 3) catch unreachable == 0.3333333333333333);
 
-    // Now we test if the function returns an error
+    // Now we test if the function returns an error if we pass a zero as
-    // if we pass a zero as denominator.
+    // denominator. But which error needs to be tested?
-    // But which error needs to be tested?
     try testing.expectError(error.???, divide(15, 0));
 }