C libs classifier(APP-120)

src/main/kotlin/app/extractors/CExtractor.kt

@@ -11,6 +11,7 @@ class CExtractor : ExtractorInterface {
     companion object {
         val LANGUAGE_NAME = "c"
         val FILE_EXTS = listOf("c")
+        val evaluator = ExtractorInterface.getLibrariesModelEvaluator(LANGUAGE_NAME)
     }
 
     override fun extract(files: List<DiffFile>): List<CommitStats> {
@@ -32,4 +33,18 @@ class CExtractor : ExtractorInterface {
 
         return imports.toList()
     }
+
+    override fun tokenize(line: String): List<String> {
+        val importRegex = Regex("""^([^\n]*#include)\s[^\n]*""")
+        val commentRegex = Regex("""^([^\n]*//)[^\n]*""")
+        var newLine = importRegex.replace(line, "")
+        newLine = commentRegex.replace(newLine, "")
+        return super.tokenize(newLine)
+    }
+
+    override fun getLineLibraries(line: String,
+                                  fileLibraries: List<String>): List<String> {
+
+        return super.getLineLibraries(line, fileLibraries, evaluator, LANGUAGE_NAME)
+    }
 }

src/main/kotlin/app/extractors/ExtractorInterface.kt

@@ -278,6 +278,15 @@ interface ExtractorInterface {
             return emptyList()
         }
 
+        // For C language.
+        // Consider line with language label being the one with high probability
+        // as not having library.
+        // Keep it while the number of libraries is small.
+        if (languageLabel == CExtractor.LANGUAGE_NAME &&
+            languageLabel in selectedCategories) {
+            return emptyList()
+        }
+
         val lineLibraries = fileLibraries.filter { it in selectedCategories }
         return lineLibraries
     }

src/test/kotlin/test/tests/extractors/ExtractorTest.kt

@@ -90,6 +90,12 @@ class ExtractorTest : Spek({
             assertExtractsLineLibraries("Tebru\\Retrofit",
                     line, PhpExtractor())
         }
+
+        it("c extractor extracts the library") {
+            val line = "grpc_test_init(argc, argv);"
+            assertExtractsLineLibraries("grpc",
+                    line, CExtractor())
+        }
     }
 
     given("code line doesn't use libraries" ) {
@@ -142,5 +148,10 @@ class ExtractorTest : Spek({
             val line = "std::cerr << status.ToString() << std::endl;"
             assertExtractsNoLibraries(line, CppExtractor())
         }
+
+        it("c extractor returns empty list") {
+            val line = "int main(int argc, char **argv) {"
+            assertExtractsNoLibraries(line, CExtractor())
+        }
     }
 })