isogram, raindrops: reject comptime solutions

exercises/practice/isogram/test_isogram.zig

@@ -3,58 +3,62 @@ const testing = std.testing;
 
 const isogram = @import("isogram.zig");
 
+fn testIsIsogram(phrase: []const u8, expected: bool) !void {
+    try testing.expectEqual(expected, isogram.isIsogram(phrase));
+}
+
 test "empty string" {
-    try testing.expect(isogram.isIsogram(""));
+    try testIsIsogram("", true);
 }
 
 test "isogram with only lower case characters" {
-    try testing.expect(isogram.isIsogram("isogram"));
+    try testIsIsogram("isogram", true);
 }
 
 test "word with one duplicated character" {
-    try testing.expect(!isogram.isIsogram("eleven"));
+    try testIsIsogram("eleven", false);
 }
 
 test "word with one duplicated character from the end of the alphabet" {
-    try testing.expect(!isogram.isIsogram("zzyzx"));
+    try testIsIsogram("zzyzx", false);
 }
 
 test "longest reported english isogram" {
-    try testing.expect(isogram.isIsogram("subdermatoglyphic"));
+    try testIsIsogram("subdermatoglyphic", true);
 }
 
 test "word with duplicated character in mixed case" {
-    try testing.expect(!isogram.isIsogram("Alphabet"));
+    try testIsIsogram("Alphabet", false);
 }
 
 test "word with duplicated character in mixed case, lowercase first" {
-    try testing.expect(!isogram.isIsogram("alphAbet"));
+    try testIsIsogram("alphAbet", false);
 }
 
 test "hypothetical isogrammic word with hyphen" {
-    try testing.expect(isogram.isIsogram("thumbscrew-japingly"));
+    try testIsIsogram("thumbscrew-japingly", true);
 }
 
 test "hypothetical word with duplicated character following hyphen" {
-    try testing.expect(!isogram.isIsogram("thumbscrew-jappingly"));
+    try testIsIsogram("thumbscrew-jappingly", false);
 }
 
 test "isogram with duplicated hyphen" {
-    try testing.expect(isogram.isIsogram("six-year-old"));
+    try testIsIsogram("six-year-old", true);
 }
 
 test "made-up name that is an isogram" {
-    try testing.expect(isogram.isIsogram("Emily Jung Schwartzkopf"));
+    try testIsIsogram("Emily Jung Schwartzkopf", true);
 }
 
 test "duplicated character in the middle" {
-    try testing.expect(!isogram.isIsogram("accentor"));
+    try testIsIsogram("accentor", false);
 }
 
 test "same first and last characters" {
-    try testing.expect(!isogram.isIsogram("angola"));
+    try testIsIsogram("angola", false);
 }
 
 test "word with duplicated character and with two hyphens" {
-    try testing.expect(!isogram.isIsogram("up-to-date"));
+    try testIsIsogram("up-to-date", false);
 }

exercises/practice/raindrops/.meta/example.zig

@@ -1,9 +1,15 @@
 const std = @import("std");
 
-pub fn convert(buffer: []u8, comptime n: u32) []const u8 {
-    const pling = if (n % 3 == 0) "Pling" else "";
-    const plang = if (n % 5 == 0) "Plang" else "";
-    const plong = if (n % 7 == 0) "Plong" else "";
-    const result = pling ++ plang ++ plong;
-    return if (result.len > 0) result else std.fmt.bufPrint(buffer, "{}", .{n}) catch unreachable;
+fn append(buffer: []u8, len: usize, sound: []const u8) usize {
+    @memcpy(buffer[len..][0..sound.len], sound);
+    return len + sound.len;
+}
+
+pub fn convert(buffer: []u8, n: u32) []const u8 {
+    var len: usize = 0;
+    if (n % 3 == 0) len = append(buffer, len, "Pling");
+    if (n % 5 == 0) len = append(buffer, len, "Plang");
+    if (n % 7 == 0) len = append(buffer, len, "Plong");
+    if (len == 0) return std.fmt.bufPrint(buffer, "{d}", .{n}) catch unreachable;
+    return buffer[0..len];
 }

exercises/practice/raindrops/test_raindrops.zig

@@ -3,10 +3,11 @@ const testing = std.testing;
 
 const raindrops = @import("raindrops.zig");
 
-fn testConvert(comptime n: u32, expected: []const u8) !void {
+fn testConvert(n: u32, expected: []const u8) !void {
     const buffer_size = 15; // The maximum length is for PlingPlangPlong
     var buffer: [buffer_size]u8 = undefined;
     const actual = raindrops.convert(&buffer, n);
+    try testing.expectEqual(@as([*]const u8, &buffer), actual.ptr);
     try testing.expectEqualStrings(expected, actual);
 }
 

generators/exercises/isogram.py

@@ -1,8 +1,13 @@
-from lib import zstr
+from lib import zbool, zstr
+
+HEADER = """
+fn testIsIsogram(phrase: []const u8, expected: bool) !void {
+    try testing.expectEqual(expected, isogram.isIsogram(phrase));
+}
+"""
 
 
 def gen_case(case):
-    phrase = case["input"]["phrase"]
-    expected = case["expected"]
-    neg = "" if expected else "!"
-    return f"    try testing.expect({neg}isogram.isIsogram({zstr(phrase)}));\n"
+    phrase = zstr(case["input"]["phrase"])
+    expected = zbool(case["expected"])
+    return f"    try testIsIsogram({phrase}, {expected});\n"

generators/exercises/raindrops.py

@@ -3,10 +3,11 @@
 IMPORT_SELF = True
 
 HEADER = """
-fn testConvert(comptime n: u32, expected: []const u8) !void {
+fn testConvert(n: u32, expected: []const u8) !void {
     const buffer_size = 15; // The maximum length is for PlingPlangPlong
     var buffer: [buffer_size]u8 = undefined;
     const actual = raindrops.convert(&buffer, n);
+    try testing.expectEqual(@as([*]const u8, &buffer), actual.ptr);
     try testing.expectEqualStrings(expected, actual);
 }
 """