using the earliest version with the exception when there are no pragma statements

Author: Janther

src/slang-utils/create-parser.ts

@@ -1,13 +1,14 @@
 import { NonterminalKind } from '@nomicfoundation/slang/cst';
 import { Parser } from '@nomicfoundation/slang/parser';
 import { LanguageFacts } from '@nomicfoundation/slang/utils';
-import { maxSatisfying } from 'semver';
+import { minSatisfying } from 'semver';
 
 import type { ParseOutput } from '@nomicfoundation/slang/parser';
 import type { ParserOptions } from 'prettier';
 import type { AstNode } from '../slang-nodes/types.js';
 
 const supportedVersions = LanguageFacts.allVersions();
+const supportedLength = supportedVersions.length;
 
 function parserAndOutput(
   text: string,
@@ -24,7 +25,7 @@ export function createParser(
   text: string,
   options: ParserOptions<AstNode>
 ): { parser: Parser; parseOutput: ParseOutput } {
-  const compiler = maxSatisfying(supportedVersions, options.compiler);
+  const compiler = minSatisfying(supportedVersions, options.compiler);
   if (compiler) {
     const result = parserAndOutput(text, compiler);
 
@@ -40,10 +41,11 @@ export function createParser(
     return result;
   }
   const inferredRanges: string[] = LanguageFacts.inferLanguageVersions(text);
+  const inferredLength = inferredRanges.length;
 
   const result = parserAndOutput(
     text,
-    inferredRanges[inferredRanges.length - 1]
+    inferredRanges[inferredLength === supportedLength ? inferredLength - 1 : 0]
   );
 
   if (!result.parseOutput.isValid())

tests/unit/slang-utils/create-parser.test.js

@@ -9,7 +9,7 @@ describe('inferLanguage', function () {
     {
       description: 'Caret range',
       source: `pragma solidity ^0.7.0;`,
-      version: '0.7.6'
+      version: '0.7.0'
     },
     {
       description: 'Pinned version',
@@ -83,8 +83,10 @@ describe('inferLanguage', function () {
     {
       description:
         'should use the latest version if the range is outside the supported versions',
-      source: `pragma solidity ^0.8.27;`,
-      version: latestSupportedVersion
+      source: `pragma solidity ^10.0.0;`,
+      version: latestSupportedVersion,
+      // TODO: unskip this test when slack fixes the error with ranges outside the supported versions.
+      skip: true
     }
   ];
 
@@ -99,9 +101,6 @@ describe('inferLanguage', function () {
     let { parser } = createParser(`contract Foo {}`, options);
     expect(parser.languageVersion).toEqual(latestSupportedVersion);
 
-    ({ parser } = createParser(`contract Foo {}`, options));
-    expect(parser.languageVersion).toEqual(latestSupportedVersion);
-
     // ({ parser } = createParser(`contract Foo {byte bar;}`, options));
     // expect(parser.languageVersion).toEqual('0.7.6');
   });
@@ -118,7 +117,7 @@ describe('inferLanguage', function () {
     expect(parser.languageVersion).toEqual('0.8.2');
 
     ({ parser } = createParser(`pragma solidity ^0.8.0;`, {}));
-    expect(parser.languageVersion).toEqual(latestSupportedVersion);
+    expect(parser.languageVersion).toEqual('0.8.0');
   });
 
   test('should throw an error if there are incompatible ranges', function () {