Easier fix

remix-tests/src/compiler.js

@@ -26,16 +26,16 @@ function compileFileOrFiles (filename, isDirectory, cb) {
   filepath = (isDirectory ? filename : path.dirname(filename))
 
   fs.readdirSync(filepath).forEach(file => {
-    // only process .sol files named *_test.sol
-    if (/_test.sol$/.test(file)) {
+    // only process .sol files
+    if (file.split('.').pop() === 'sol') {
       let c = fs.readFileSync(path.join(filepath, file)).toString()
       const s = /^(import)\s['"](remix_tests.sol|tests.sol)['"];/gm
-      if (!s.test(c)) {
+      if (file.indexOf('_test.sol') > 0 && c.regexIndexOf(s) < 0) {
         c = c.replace(/(pragma solidity \^?\d+\.\d+\.\d+;)/, '$1\nimport \'remix_tests.sol\';')
       }
       sources[file] = { content: c }
     }
-  })
+  })  
 
   async.waterfall([
     function loadCompiler (next) {