KT-15363 Collection builders: improve tests and samples

libraries/stdlib/samples/test/samples/collections/builders.kt

@@ -22,15 +22,15 @@ class Builders {
     class Sets {
         @Sample
         fun buildSetSample() {
-            val x = setOf('b', 'c')
+            val x = setOf('a', 'b')
 
             val y = buildSet(x.size + 2) {
-                add('a')
+                add('b')
                 addAll(x)
-                add('d')
+                add('c')
             }
 
-            assertPrints(y, "[a, b, c, d]")
+            assertPrints(y, "[b, a, c]")
         }
     }
 
@@ -41,11 +41,12 @@ class Builders {
 
             val y = buildMap<Char, Int>(x.size + 2) {
                 put('a', 1)
+                put('c', 0)
                 putAll(x)
                 put('d', 4)
             }
 
-            assertPrints(y, "{a=1, b=2, c=3, d=4}")
+            assertPrints(y, "{a=1, c=3, b=2, d=4}")
         }
     }
 }

libraries/stdlib/test/collections/ContainerBuilderTest.kt

@@ -3,7 +3,8 @@ package test.collections
 import kotlin.test.*
 
 class ContainerBuilderTest {
-    @Test fun buildList() {
+    @Test
+    fun buildList() {
         val x = buildList {
             add('b')
             add('c')
@@ -16,36 +17,34 @@ class ContainerBuilderTest {
         }
 
         assertEquals(listOf('a', 'b', 'c', 'd'), y)
-    }
 
-    @Test fun exceptionIsThrownIfExpectedListSizeIsNegative() {
-        assertFailsWith(IllegalArgumentException::class) {
-            buildList<Any?>(-1) {}
+        assertFailsWith<IllegalArgumentException> {
+            buildList(-1) { add(0) }
         }
     }
 
-    @Test fun buildSet() {
+    @Test
+    fun buildSet() {
         val x = buildSet {
             add('b')
             add('c')
         }
 
         val y = buildSet(4) {
-            add('a')
+            add('c')
             addAll(x)
             add('d')
         }
 
-        assertEquals(setOf('a', 'b', 'c', 'd'), y)
-    }
+        assertEquals(setOf('c', 'b', 'd'), y)
 
-    @Test fun exceptionIsThrownIfExpectedSetSizeIsNegative() {
-        assertFailsWith(IllegalArgumentException::class) {
-            buildSet<Any?>(-1) {}
+        assertFailsWith<IllegalArgumentException> {
+            buildSet(-1) { add(0) }
         }
     }
 
-    @Test fun buildMap() {
+    @Test
+    fun buildMap() {
         val x = buildMap<Char, Int> {
             put('b', 2)
             put('c', 3)
@@ -53,16 +52,15 @@ class ContainerBuilderTest {
 
         val y = buildMap<Char, Int>(4) {
             put('a', 1)
+            put('c', 0)
             putAll(x)
             put('d', 4)
         }
 
-        assertEquals(mapOf('a' to 1, 'b' to 2, 'c' to 3, 'd' to 4), y)
-    }
+        assertEquals(mapOf('a' to 1, 'c' to 3, 'b' to 2, 'd' to 4), y)
 
-    @Test fun exceptionIsThrownIfExpectedMapSizeIsNegative() {
-        assertFailsWith(IllegalArgumentException::class) {
-            buildMap<Any?, Any?>(-1) {}
+        assertFailsWith<IllegalArgumentException> {
+            buildMap<String, Int>(-1) { put("x", 1) }
         }
     }
 }