fix log typo, add comments on why we prefer in process compilation

Author: yigit

core/src/main/kotlin/com/tschuchort/compiletesting/KotlinCompilation.kt

@@ -506,7 +506,10 @@ class KotlinCompilation : AbstractKotlinCompilation<K2JVMCompilerArguments>() {
         if(jdkHome != null && jdkHome!!.canonicalPath != processJdkHome.canonicalPath) {
             /* If a JDK home is given, try to run javac from there so it uses the same JDK
                as K2JVMCompiler. Changing the JDK of the system java compiler via the
-               "--system" and "-bootclasspath" options is not so easy. */
+               "--system" and "-bootclasspath" options is not so easy.
+               If the jdkHome is the same as the current process, we still run an in process compilation because it is
+               expensive to fork a process to compile.
+               */
             log("compiling java in a sub-process because a jdkHome is specified")
             val jdkBinFile = File(jdkHome, "bin")
             check(jdkBinFile.exists()) { "No JDK bin folder found at: ${jdkBinFile.toPath()}" }
@@ -539,7 +542,7 @@ class KotlinCompilation : AbstractKotlinCompilation<K2JVMCompilerArguments>() {
 			val isJavac9OrLater = isJdk9OrLater()
 			val javacArgs = baseJavacArgs(isJavac9OrLater).apply {
 				if (jdkHome == null) {
-				    log("jdkHome is set to null, removing booth classpath from java compilation")
+				    log("jdkHome is set to null, removing boot classpath from java compilation")
 					// erase bootclasspath or JDK path because no JDK was specified
 					if (isJavac9OrLater)
 						addAll("--system", "none")

core/src/test/kotlin/com/tschuchort/compiletesting/KotlinCompilationTests.kt

@@ -184,7 +184,7 @@ class KotlinCompilationTests {
 		assertThat(result.exitCode).isEqualTo(ExitCode.COMPILATION_ERROR)
 		assertThat(result.messages).contains("Unable to find package java.lang")
 		assertThat(result.messages).contains(
-			"jdkHome is set to null, removing booth classpath from java compilation"
+			"jdkHome is set to null, removing boot classpath from java compilation"
 		)
 	}
 
@@ -826,7 +826,7 @@ class KotlinCompilationTests {
 			"jdkHome is not specified. Using system java compiler of the host process."
 		)
 		assertThat(result.messages).doesNotContain(
-			"jdkHome is set to null, removing booth classpath from java compilation"
+			"jdkHome is set to null, removing boot classpath from java compilation"
 		)
 	}
 
@@ -855,7 +855,7 @@ class KotlinCompilationTests {
 			"compiling java in a sub-process because a jdkHome is specified"
 		)
 		assertThat(logs).doesNotContain(
-			"jdkHome is set to null, removing booth classpath from java compilation"
+			"jdkHome is set to null, removing boot classpath from java compilation"
 		)
 	}