Using Slang's language inference tool

package.json

@@ -85,14 +85,14 @@
   "devDependencies": {
     "@babel/code-frame": "^7.27.1",
     "@eslint/eslintrc": "^3.3.1",
-    "@eslint/js": "^9.28.0",
+    "@eslint/js": "^9.29.0",
     "@types/jest": "^29.5.14",
     "@types/semver": "^7.7.0",
-    "@typescript-eslint/eslint-plugin": "^8.34.0",
-    "@typescript-eslint/parser": "^8.34.0",
+    "@typescript-eslint/eslint-plugin": "^8.34.1",
+    "@typescript-eslint/parser": "^8.34.1",
     "c8": "^10.1.3",
     "cross-env": "^7.0.3",
-    "eslint": "^9.28.0",
+    "eslint": "^9.29.0",
     "eslint-config-prettier": "^10.1.5",
     "esm-utils": "^4.4.2",
     "globals": "^16.2.0",

src/slang-utils/create-parser.ts

@@ -1,145 +1,61 @@
-import { VersionExpressionSets as SlangVersionExpressionSets } from '@nomicfoundation/slang/ast';
-import { NonterminalKind, Query } from '@nomicfoundation/slang/cst';
+import { NonterminalKind } from '@nomicfoundation/slang/cst';
 import { Parser } from '@nomicfoundation/slang/parser';
 import { LanguageFacts } from '@nomicfoundation/slang/utils';
-import {
-  maxSatisfying,
-  minSatisfying,
-  minor,
-  major,
-  satisfies,
-  validRange
-} from 'semver';
-import { VersionExpressionSets } from '../slang-nodes/VersionExpressionSets.js';
+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;
 
-const milestoneVersions = Array.from(
-  supportedVersions.reduce((minorRanges, version) => {
-    minorRanges.add(`^${major(version)}.${minor(version)}.0`);
-    return minorRanges;
-  }, new Set<string>())
-)
-  .reverse()
-  .reduce((versions: string[], range) => {
-    versions.push(maxSatisfying(supportedVersions, range)!);
-    versions.push(minSatisfying(supportedVersions, range)!);
-    return versions;
-  }, []);
-
-const queries = [
-  Query.create('[VersionPragma @versionRanges [VersionExpressionSets]]')
-];
-
-let parser: Parser;
+function parserAndOutput(
+  text: string,
+  version: string
+): { parser: Parser; parseOutput: ParseOutput } {
+  const parser = Parser.create(version);
+  return {
+    parser,
+    parseOutput: parser.parseNonterminal(NonterminalKind.SourceUnit, text)
+  };
+}
 
 export function createParser(
   text: string,
   options: ParserOptions<AstNode>
-): [Parser, ParseOutput] {
-  const compiler = maxSatisfying(supportedVersions, options.compiler);
+): { parser: Parser; parseOutput: ParseOutput } {
+  const compiler = minSatisfying(supportedVersions, options.compiler);
   if (compiler) {
-    if (!parser || parser.languageVersion !== compiler) {
-      parser = Parser.create(compiler);
-    }
-    return [parser, parser.parseNonterminal(NonterminalKind.SourceUnit, text)];
-  }
-
-  let isCachedParser = false;
-  if (parser) {
-    isCachedParser = true;
-  } else {
-    parser = Parser.create(milestoneVersions[0]);
-  }
-
-  let parseOutput;
-  let inferredRanges: string[] = [];
-
-  try {
-    parseOutput = parser.parseNonterminal(NonterminalKind.SourceUnit, text);
-    inferredRanges = tryToCollectPragmas(parseOutput, parser, isCachedParser);
-  } catch {
-    for (
-      let i = isCachedParser ? 0 : 1;
-      i <= milestoneVersions.length;
-      i += 1
-    ) {
-      try {
-        const version = milestoneVersions[i];
-        parser = Parser.create(version);
-        parseOutput = parser.parseNonterminal(NonterminalKind.SourceUnit, text);
-        inferredRanges = tryToCollectPragmas(parseOutput, parser);
-        break;
-      } catch {
-        continue;
-      }
-    }
-  }
-
-  const satisfyingVersions = inferredRanges.reduce(
-    (versions, inferredRange) => {
-      if (!validRange(inferredRange)) {
-        throw new Error(
-          `Couldn't infer any version from the ranges in the pragmas${options.filepath ? ` for file ${options.filepath}` : ''}`
-        );
-      }
-      return versions.filter((supportedVersion) =>
-        satisfies(supportedVersion, inferredRange)
+    const result = parserAndOutput(text, compiler);
+
+    if (!result.parseOutput.isValid())
+      throw new Error(
+        'We encoutered the following syntax error:\n\n\t' +
+          result.parseOutput.errors()[0].message +
+          '\n\nBased on the compiler option provided, we inferred your code to be using Solidity version ' +
+          result.parser.languageVersion +
+          '. If you would like to change that, specify a different version in your `.prettierrc` file.'
       );
-    },
-    supportedVersions
-  );
-
-  const inferredVersion =
-    satisfyingVersions.length > 0
-      ? satisfyingVersions[satisfyingVersions.length - 1]
-      : supportedVersions[supportedVersions.length - 1];
 
-  if (inferredVersion !== parser.languageVersion) {
-    parser = Parser.create(inferredVersion);
-    parseOutput = parser.parseNonterminal(NonterminalKind.SourceUnit, text);
+    return result;
   }
+  const inferredRanges: string[] = LanguageFacts.inferLanguageVersions(text);
+  const inferredLength = inferredRanges.length;
 
-  // eslint-disable-next-line @typescript-eslint/no-unnecessary-type-assertion
-  return [parser, parseOutput!];
-}
-
-function tryToCollectPragmas(
-  parseOutput: ParseOutput,
-  parser: Parser,
-  isCachedParser = false
-): string[] {
-  const matches = parseOutput.createTreeCursor().query(queries);
-  const ranges: string[] = [];
-
-  let match;
-  while ((match = matches.next())) {
-    const versionRange = new SlangVersionExpressionSets(
-      match.captures.versionRanges[0].node.asNonterminalNode()!
-    );
-    ranges.push(
-      // Replace all comments that could be in the expression with whitespace
-      new VersionExpressionSets(versionRange).comments.reduce(
-        (range, comment) => range.replace(comment.value, ' '),
-        versionRange.cst.unparse()
-      )
-    );
-  }
+  const result = parserAndOutput(
+    text,
+    inferredRanges[inferredLength === supportedLength ? inferredLength - 1 : 0]
+  );
 
-  if (ranges.length === 0) {
-    // If we didn't find pragmas but succeeded parsing the source we keep it.
-    if (!isCachedParser && parseOutput.isValid()) {
-      return [parser.languageVersion];
-    }
-    // Otherwise we throw.
+  if (!result.parseOutput.isValid())
     throw new Error(
-      `Using version ${parser.languageVersion} did not find any pragma statement and does not parse without errors.`
+      'We encoutered the following syntax error:\n\n\t' +
+        result.parseOutput.errors()[0].message +
+        '\n\nBased on the pragma statements, we inferred your code to be using Solidity version ' +
+        result.parser.languageVersion +
+        '. If you would like to change that, update the pragmas in your source file, or specify a version in your `.prettierrc` file.'
     );
-  }
 
-  return ranges;
+  return result;
 }

src/slangSolidityParser.ts

@@ -11,17 +11,14 @@ export default function parse(
   text: string,
   options: ParserOptions<AstNode>
 ): AstNode {
-  const [parser, parseOutput] = createParser(text, options);
+  const { parser, parseOutput } = createParser(text, options);
 
-  if (parseOutput.isValid()) {
-    // We update the compiler version by the inferred one.
-    options.compiler = parser.languageVersion;
-    const parsed = new SourceUnit(
-      new SlangSourceUnit(parseOutput.tree.asNonterminalNode()),
-      options
-    );
-    clearOffsets();
-    return parsed;
-  }
-  throw new Error(parseOutput.errors()[0].message);
+  // We update the compiler version by the inferred one.
+  options.compiler = parser.languageVersion;
+  const parsed = new SourceUnit(
+    new SlangSourceUnit(parseOutput.tree.asNonterminalNode()),
+    options
+  );
+  clearOffsets();
+  return parsed;
 }

tests/config/run-format-test.js

@@ -334,7 +334,7 @@ async function runTest({
       // same for ANTLR unless it was already given as an option.
       compiler:
         formatOptions.compiler ||
-        createParser(code, formatOptions)[0].languageVersion,
+        createParser(code, formatOptions).parser.languageVersion,
       parser: "antlr",
       plugins: await getPlugins(),
     });

tests/format/AllSolidityFeatures/AllSolidityFeatures.sol

@@ -1,8 +1,4 @@
 // Examples taken from the Solidity documentation online.
-
-// for pragma version numbers, see https://docs.npmjs.com/misc/semver#versions
-pragma solidity 0.4.0;
-pragma solidity ^0.4.0;
 pragma experimental ABIEncoderV2;
 
 import "SomeFile.sol";

tests/format/AllSolidityFeatures/__snapshots__/format.test.js.snap

@@ -7,10 +7,6 @@ printWidth: 80
                                                                                 | printWidth
 =====================================input======================================
 // Examples taken from the Solidity documentation online.
-
-// for pragma version numbers, see https://docs.npmjs.com/misc/semver#versions
-pragma solidity 0.4.0;
-pragma solidity ^0.4.0;
 pragma experimental ABIEncoderV2;
 
 import "SomeFile.sol";
@@ -370,10 +366,6 @@ using {    add as   +  , sub   } for   Fixed18 global  ;
 
 =====================================output=====================================
 // Examples taken from the Solidity documentation online.
-
-// for pragma version numbers, see https://docs.npmjs.com/misc/semver#versions
-pragma solidity 0.4.0;
-pragma solidity ^0.4.0;
 pragma experimental ABIEncoderV2;
 
 import "SomeFile.sol";

tests/format/AllSolidityFeaturesV0.4.26/__snapshots__/format.test.js.snap

@@ -1,7 +1,8 @@
-// Jest Snapshot v1, https://goo.gl/fbAQLP
+// Jest Snapshot v1, https://jestjs.io/docs/snapshot-testing
 
-exports[`AllSolidityFeatures.sol format 1`] = `
+exports[`AllSolidityFeatures.sol - {"compiler":"0.4.26"} format 1`] = `
 ====================================options=====================================
+compiler: "0.4.26"
 parsers: ["slang"]
 printWidth: 80
                                                                                 | printWidth

tests/format/AllSolidityFeaturesV0.4.26/format.test.js

@@ -1 +1 @@
-runFormatTest(import.meta, ['slang']);
+runFormatTest(import.meta, ['slang'], { compiler: '0.4.26' });

tests/format/BasicIterator/__snapshots__/format.test.js.snap

@@ -1,7 +1,8 @@
-// Jest Snapshot v1, https://goo.gl/fbAQLP
+// Jest Snapshot v1, https://jestjs.io/docs/snapshot-testing
 
-exports[`BasicIterator.sol format 1`] = `
+exports[`BasicIterator.sol - {"compiler":"0.4.26"} format 1`] = `
 ====================================options=====================================
+compiler: "0.4.26"
 parsers: ["slang"]
 printWidth: 80
                                                                                 | printWidth

tests/format/BasicIterator/format.test.js

@@ -1 +1 @@
-runFormatTest(import.meta, ['slang']);
+runFormatTest(import.meta, ['slang'], { compiler: '0.4.26' });

tests/format/Comments/Comments.sol

@@ -1,6 +1,3 @@
-pragma solidity ^0.4.29;
-
-
 contract Comments1 {
   /* solhint-disable var-name-mixedcase */
 IEIP712DomainSeparator private EIP712domainSeparator;

tests/format/Comments/__snapshots__/format.test.js.snap

@@ -6,9 +6,6 @@ parsers: ["slang"]
 printWidth: 80
                                                                                 | printWidth
 =====================================input======================================
-pragma solidity ^0.4.29;
-
-
 contract Comments1 {
   /* solhint-disable var-name-mixedcase */
 IEIP712DomainSeparator private EIP712domainSeparator;
@@ -178,8 +175,6 @@ contract Comments13 {
   }
 }
 =====================================output=====================================
-pragma solidity ^0.4.29;
-
 contract Comments1 {
     /* solhint-disable var-name-mixedcase */
     IEIP712DomainSeparator private EIP712domainSeparator;

tests/format/FunctionDefinitionsV0.5.0/__snapshots__/format.test.js.snap

@@ -1,7 +1,8 @@
-// Jest Snapshot v1, https://goo.gl/fbAQLP
+// Jest Snapshot v1, https://jestjs.io/docs/snapshot-testing
 
-exports[`FunctionDefinitions.sol format 1`] = `
+exports[`FunctionDefinitions.sol - {"compiler":"0.5.17"} format 1`] = `
 ====================================options=====================================
+compiler: "0.5.17"
 parsers: ["slang"]
 printWidth: 80
                                                                                 | printWidth

tests/format/FunctionDefinitionsV0.5.0/format.test.js

@@ -1 +1 @@
-runFormatTest(import.meta, ['slang']);
+runFormatTest(import.meta, ['slang'], { compiler: '0.5.17' });

tests/format/FunctionDefinitionsv0.5.0/__snapshots__/format.test.js.snap

@@ -1,7 +1,8 @@
-// Jest Snapshot v1, https://goo.gl/fbAQLP
+// Jest Snapshot v1, https://jestjs.io/docs/snapshot-testing
 
-exports[`FunctionDefinitions.sol format 1`] = `
+exports[`FunctionDefinitions.sol - {"compiler":"0.5.17"} format 1`] = `
 ====================================options=====================================
+compiler: "0.5.17"
 parsers: ["slang"]
 printWidth: 80
                                                                                 | printWidth

tests/format/FunctionDefinitionsv0.5.0/format.test.js

@@ -1 +1 @@
-runFormatTest(import.meta, ['slang']);
+runFormatTest(import.meta, ['slang'], { compiler: '0.5.17' });

tests/format/IndexOf/__snapshots__/format.test.js.snap

@@ -1,7 +1,8 @@
-// Jest Snapshot v1, https://goo.gl/fbAQLP
+// Jest Snapshot v1, https://jestjs.io/docs/snapshot-testing
 
-exports[`IndexOf.sol format 1`] = `
+exports[`IndexOf.sol - {"compiler":"0.4.26"} format 1`] = `
 ====================================options=====================================
+compiler: "0.4.26"
 parsers: ["slang"]
 printWidth: 80
                                                                                 | printWidth

tests/format/IndexOf/format.test.js

@@ -1 +1 @@
-runFormatTest(import.meta, ['slang']);
+runFormatTest(import.meta, ['slang'], { compiler: '0.4.26' });

tests/format/MemberAccess/__snapshots__/format.test.js.snap

@@ -1,7 +1,8 @@
-// Jest Snapshot v1, https://goo.gl/fbAQLP
+// Jest Snapshot v1, https://jestjs.io/docs/snapshot-testing
 
-exports[`MemberAccess.sol format 1`] = `
+exports[`MemberAccess.sol - {"compiler":"0.6.12"} format 1`] = `
 ====================================options=====================================
+compiler: "0.6.12"
 parsers: ["slang"]
 printWidth: 80
                                                                                 | printWidth

tests/format/MemberAccess/format.test.js

@@ -1 +1 @@
-runFormatTest(import.meta, ['slang']);
+runFormatTest(import.meta, ['slang'], { compiler: '0.6.12' });