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Add Language Support

A good place to start looking at is here: https://github.com/searleser97/cpbooster/blob/33f274c030015bb555824d5ba7a4c1b11776257a/app/src/Test/TesterFactory/TesterFactory.ts

where you will find that we have three main clases that represent compiled, interpreted and mixed languages.

Interpreted#

Usually, all interpreted languages have the same syntax to run a file:

interpreter filename.[extension]

e.g.

$ python filename.py
$ ruby filename.rb
$ node filname.js
...

therefore, cpbooster should support absolutely all interpreted languages.

The issue comes when we use either compiled or interpreted languages, specifically when it comes to indicate the name for the executable (binary) file.

Compiled#

Compilers like gcc, clang, rustc, go, ... use the -o argument to indicate the name for the executable file.

e.g.

gcc filename.cpp -o myexecutable.exe
go build filename.go -o myexecutable.exe
rustc filename.rs -o myexecutable.exe
...

However, there might exist some other compilers that do not follow this convention and they probably use a different argument, to solve this we have the following function

static getFileNameOptionForCompilerCommand(compilerCommand: string): string {
return CompiledTester.fileNameOptionForCommand.get(compilerCommand) ?? "-o";
}

https://github.com/searleser97/cpbooster/blob/33f274c030015bb555824d5ba7a4c1b11776257a/app/src/Test/TesterFactory/CompiledTester.ts#L111-L113

which uses a Map (hash table) to retrieve the correct argument name depending on the compiler command (gcc, g++, csc, go, ...), if the compiler does not exist in the hash table (Map) it defaults to the -o argument name.

private static fileNameOptionForCommand: Map<string, string> = new Map([
[NonStandardCompilers.mcs, "-out:"], // csharp compiler
[NonStandardCompilers.csc, "/out:"] // csharp compiler
]);

https://github.com/searleser97/cpbooster/blob/33f274c030015bb555824d5ba7a4c1b11776257a/app/src/Test/TesterFactory/CompiledTester.ts#L37-L40

notice that in the hash table (Map) we just have msc and csc which are C# compilers, this is because all the tested languages except for C# use the -o argument therefore there is no need to insert them into the hash table.

Now let's actually talk about C# compilers and how they conflict with the standard format. It turns out that these compilers not just use a different argument name to sepecify the executable name, but they also force us to write the name of the executable together with the argument name (i.e. not separated by a space)

e.g.

mcs -out:myexecutable.exe filename.cs
csc /out:myexecutable.exe filename.cs

to solve this when we compile we have an special condition, which basically checks if the compiler is NOT standard (i.e. csc and mcs) then join/concatenate the argument name with the executable name.

if (Object.keys(NonStandardCompilers).includes(compilerCommand)) {
args.push(
CompiledTester.getFileNameOptionForCompilerCommand(compilerCommand) +
this.getDefaultExecutableFileName(debug)
);
} else {
args.push(
CompiledTester.getFileNameOptionForCompilerCommand(compilerCommand),
this.getDefaultExecutableFileName(debug)
);
}

https://github.com/searleser97/cpbooster/blob/33f274c030015bb555824d5ba7a4c1b11776257a/app/src/Test/TesterFactory/CompiledTester.ts#L144-L154

export enum NonStandardCompilers {
mcs = "mcs",
csc = "csc",
}

https://github.com/searleser97/cpbooster/blob/33f274c030015bb555824d5ba7a4c1b11776257a/app/src/Test/TesterFactory/CompiledTester.ts#L31-L34

Mixed#

mixed languages are the ones that are compiled with one command but executed with another one (not counting ./executable.exe format as command) e.g. programs written in Java are compiled using the javac command and then executed using the java command, something similar happens with languages like Kotlin and Scala.

Usually, these languages generate a .class file after compilation, this .class file usually has the same name as the source file name or the same name as the class declared inside it. cpbooster takes advantage of this behavior and therefore, no extra code is written to name the executables (.class files), except for kotlin which adds Kt to the executable name, we have that case covered with a simple if condition here:

getExecutableFileName(): string {
return `${this.getExecutableFileNameNoExtension()}${
this.langExtension === LangExtensions.kotlin ? "Kt" : ""
}.class`;
}

https://github.com/searleser97/cpbooster/blob/33f274c030015bb555824d5ba7a4c1b11776257a/app/src/Test/TesterFactory/MixedTester.ts#L36

note

Currently, to guarantee the correct behavior of cpbooster, the class name should match with the source file name, since some languages use the class name as the executable (.class) name instead of the source file name.

Which leads to a possible contribution related with the "templates" for languages that require the declaration of a class. We can add the concept of cpbooster-variables which will be formatted strings that will get replaced with some information, like filename or date, etc

e.g.

template.java#
/**
* Date Time: $${DateTime}$$
*/
import java.util.*;
public class $${FileName}$$ <-- just a suggested syntax not sure if its the best
{
public static void main(String[] args)
{
}
}

then if we create a file ProblemC.java with cpbooster the file will look like this:

/**
* DateTime: 13-07-2022 13:30 <-- $${DateTime}$$ was replaced with the "current" date time
*/
import java.util.*;
public class ProblemC <-- $${FileName}$$ was replaced with ProblemC
{
public static void main(String[] args)
{
}
}

one thing to note here is that we will also need to force the file name to have the first letter capitalized (in uppercase), since some mixed languages do not allow to create classes that do not have the first letter in uppercase.

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