text: "use strict";
  /**
   * @license
   * Copyright 2017 Palantir Technologies, Inc.
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  Object.defineProperty(exports, "__esModule", { value: true });
  var tslib_1 = require("tslib");
  var utils = require("tsutils");
  var ts = require("typescript");
  var Lint = require("../index");
  var utils_1 = require("../utils");
  var adjacentOverloadSignaturesRule_1 = require("./adjacentOverloadSignaturesRule");
  var Rule = /** @class */ (function (_super) {
      tslib_1.__extends(Rule, _super);
      function Rule() {
          return _super !== null && _super.apply(this, arguments) || this;
      }
      /* tslint:enable:object-literal-sort-keys */
      Rule.FAILURE_STRING_OMITTING_SINGLE_PARAMETER = function (otherLine) {
          return Rule.FAILURE_STRING_START(otherLine) + " with an optional parameter.";
      };
      Rule.FAILURE_STRING_OMITTING_REST_PARAMETER = function (otherLine) {
          return Rule.FAILURE_STRING_START(otherLine) + " with a rest parameter.";
      };
      Rule.FAILURE_STRING_SINGLE_PARAMETER_DIFFERENCE = function (otherLine, type1, type2) {
          return Rule.FAILURE_STRING_START(otherLine) + " taking `" + type1 + " | " + type2 + "`.";
      };
      Rule.FAILURE_STRING_START = function (otherLine) {
          // For only 2 overloads we don't need to specify which is the other one.
          var overloads = otherLine === undefined
              ? "These overloads"
              : "This overload and the one on line " + otherLine;
          return overloads + " can be combined into one signature";
      };
      Rule.prototype.apply = function (sourceFile) {
          return this.applyWithFunction(sourceFile, walk);
      };
      /* tslint:disable:object-literal-sort-keys */
      Rule.metadata = {
          ruleName: "unified-signatures",
          description: "Warns for any two overloads that could be unified into one by using a union or an optional/rest parameter.",
          optionsDescription: "Not configurable.",
          options: null,
          optionExamples: [true],
          type: "typescript",
          typescriptOnly: true,
      };
      return Rule;
  }(Lint.Rules.AbstractRule));
  exports.Rule = Rule;
  function walk(ctx) {
      var sourceFile = ctx.sourceFile;
      checkStatements(sourceFile.statements);
      return ts.forEachChild(sourceFile, function cb(node) {
          switch (node.kind) {
              case ts.SyntaxKind.ModuleBlock:
                  checkStatements(node.statements);
                  break;
              case ts.SyntaxKind.InterfaceDeclaration:
              case ts.SyntaxKind.ClassDeclaration: {
                  var _a = node, members = _a.members, typeParameters = _a.typeParameters;
                  checkMembers(members, typeParameters);
                  break;
              }
              case ts.SyntaxKind.TypeLiteral:
                  checkMembers(node.members);
          }
          return ts.forEachChild(node, cb);
      });
      function checkStatements(statements) {
          addFailures(checkOverloads(statements, undefined, function (statement) {
              if (utils.isFunctionDeclaration(statement)) {
                  var body = statement.body, name = statement.name;
                  return body === undefined && name !== undefined
                      ? { signature: statement, key: name.text }
                      : undefined;
              }
              else {
                  return undefined;
              }
          }));
      }
      function checkMembers(members, typeParameters) {
          addFailures(checkOverloads(members, typeParameters, function (member) {
              switch (member.kind) {
                  case ts.SyntaxKind.CallSignature:
                  case ts.SyntaxKind.ConstructSignature:
                  case ts.SyntaxKind.MethodSignature:
                      break;
                  case ts.SyntaxKind.MethodDeclaration:
                  case ts.SyntaxKind.Constructor:
                      if (member.body !==
                          undefined) {
                          return undefined;
                      }
                      break;
                  default:
                      return undefined;
              }
              var signature = member;
              var key = adjacentOverloadSignaturesRule_1.getOverloadKey(signature);
              return key === undefined ? undefined : { signature: signature, key: key };
          }));
      }
      function addFailures(failures) {
          for (var _i = 0, failures_1 = failures; _i < failures_1.length; _i++) {
              var failure = failures_1[_i];
              var unify = failure.unify, only2 = failure.only2;
              switch (unify.kind) {
                  case "single-parameter-difference": {
                      var p0 = unify.p0, p1 = unify.p1;
                      var lineOfOtherOverload = only2 ? undefined : getLine(p0.getStart());
                      ctx.addFailureAtNode(p1, Rule.FAILURE_STRING_SINGLE_PARAMETER_DIFFERENCE(lineOfOtherOverload, typeText(p0), typeText(p1)));
                      break;
                  }
                  case "extra-parameter": {
                      var extraParameter = unify.extraParameter, otherSignature = unify.otherSignature;
                      var lineOfOtherOverload = only2 ? undefined : getLine(otherSignature.pos);
                      ctx.addFailureAtNode(extraParameter, extraParameter.dotDotDotToken !== undefined
                          ? Rule.FAILURE_STRING_OMITTING_REST_PARAMETER(lineOfOtherOverload)
                          : Rule.FAILURE_STRING_OMITTING_SINGLE_PARAMETER(lineOfOtherOverload));
                  }
              }
          }
      }
      function getLine(pos) {
          return ts.getLineAndCharacterOfPosition(sourceFile, pos).line + 1;
      }
  }
  function checkOverloads(signatures, typeParameters, getOverload) {
      var result = [];
      var isTypeParameter = getIsTypeParameter(typeParameters);
      for (var _i = 0, _a = collectOverloads(signatures, getOverload); _i < _a.length; _i++) {
          var overloads = _a[_i];
          if (overloads.length === 2) {
              var unify = compareSignatures(overloads[0], overloads[1], isTypeParameter);
              if (unify !== undefined) {
                  result.push({ unify: unify, only2: true });
              }
          }
          else {
              forEachPair(overloads, function (a, b) {
                  var unify = compareSignatures(a, b, isTypeParameter);
                  if (unify !== undefined) {
                      result.push({ unify: unify, only2: false });
                  }
              });
          }
      }
      return result;
  }
  function compareSignatures(a, b, isTypeParameter) {
      if (!signaturesCanBeUnified(a, b, isTypeParameter)) {
          return undefined;
      }
      return a.parameters.length === b.parameters.length
          ? signaturesDifferBySingleParameter(a.parameters, b.parameters)
          : signaturesDifferByOptionalOrRestParameter(a.parameters, b.parameters);
  }
  function signaturesCanBeUnified(a, b, isTypeParameter) {
      // Must return the same type.
      return (typesAreEqual(a.type, b.type) &&
          // Must take the same type parameters.
          utils_1.arraysAreEqual(a.typeParameters, b.typeParameters, typeParametersAreEqual) &&
          // If one uses a type parameter (from outside) and the other doesn't, they shouldn't be joined.
          signatureUsesTypeParameter(a, isTypeParameter) ===
              signatureUsesTypeParameter(b, isTypeParameter));
  }
  /** Detect `a(x: number, y: number, z: number)` and `a(x: number, y: string, z: number)`. */
  function signaturesDifferBySingleParameter(types1, types2) {
      var index = getIndexOfFirstDifference(types1, types2, parametersAreEqual);
      if (index === undefined) {
          return undefined;
      }
      // If remaining arrays are equal, the signatures differ by just one parameter type
      if (!utils_1.arraysAreEqual(types1.slice(index + 1), types2.slice(index + 1), parametersAreEqual)) {
          return undefined;
      }
      var a = types1[index];
      var b = types2[index];
      // Can unify `a?: string` and `b?: number`. Can't unify `...args: string[]` and `...args: number[]`.
      // See https://github.com/Microsoft/TypeScript/issues/5077
      return parametersHaveEqualSigils(a, b) && a.dotDotDotToken === undefined
          ? { kind: "single-parameter-difference", p0: a, p1: b }
          : undefined;
  }
  /**
   * Detect `a(): void` and `a(x: number): void`.
   * Returns the parameter declaration (`x: number` in this example) that should be optional/rest, and overload it's a part of.
   */
  function signaturesDifferByOptionalOrRestParameter(sig1, sig2) {
      var minLength = Math.min(sig1.length, sig2.length);
      var longer = sig1.length < sig2.length ? sig2 : sig1;
      var shorter = sig1.length < sig2.length ? sig1 : sig2;
      // If one is has 2+ parameters more than the other, they must all be optional/rest.
      // Differ by optional parameters: f() and f(x), f() and f(x, ?y, ...z)
      // Not allowed: f() and f(x, y)
      for (var i = minLength + 1; i < longer.length; i++) {
          if (!parameterMayBeMissing(longer[i])) {
              return undefined;
          }
      }
      for (var i = 0; i < minLength; i++) {
          if (!typesAreEqual(sig1[i].type, sig2[i].type)) {
              return undefined;
          }
      }
      if (minLength > 0 && shorter[minLength - 1].dotDotDotToken !== undefined) {
          return undefined;
      }
      return {
          extraParameter: longer[longer.length - 1],
          kind: "extra-parameter",
          otherSignature: shorter,
      };
  }
  /** Given type parameters, returns a function to test whether a type is one of those parameters. */
  function getIsTypeParameter(typeParameters) {
      if (typeParameters === undefined) {
          return function () { return false; };
      }
      var set = new Set();
      for (var _i = 0, typeParameters_1 = typeParameters; _i < typeParameters_1.length; _i++) {
          var t = typeParameters_1[_i];
          set.add(t.getText());
      }
      return function (typeName) { return set.has(typeName); };
  }
  /** True if any of the outer type parameters are used in a signature. */
  function signatureUsesTypeParameter(sig, isTypeParameter) {
      return sig.parameters.some(function (p) { return p.type !== undefined && typeContainsTypeParameter(p.type) === true; });
      function typeContainsTypeParameter(type) {
          if (utils.isTypeReferenceNode(type)) {
              var typeName = type.typeName;
              if (typeName.kind === ts.SyntaxKind.Identifier && isTypeParameter(typeName.text)) {
                  return true;
              }
          }
          return ts.forEachChild(type, typeContainsTypeParameter);
      }
  }
  /**
   * Given all signatures, collects an array of arrays of signatures which are all overloads.
   * Does not rely on overloads being adjacent. This is similar to code in adjacentOverloadSignaturesRule.ts, but not the same.
   */
  function collectOverloads(nodes, getOverload) {
      var map = new Map();
      for (var _i = 0, nodes_1 = nodes; _i < nodes_1.length; _i++) {
          var sig = nodes_1[_i];
          var overload = getOverload(sig);
          if (overload === undefined) {
              continue;
          }
          var signature = overload.signature, key = overload.key;
          var overloads = map.get(key);
          if (overloads !== undefined) {
              overloads.push(signature);
          }
          else {
              map.set(key, [signature]);
          }
      }
      return Array.from(map.values());
  }
  function parametersAreEqual(a, b) {
      return parametersHaveEqualSigils(a, b) && typesAreEqual(a.type, b.type);
  }
  /** True for optional/rest parameters. */
  function parameterMayBeMissing(p) {
      return p.dotDotDotToken !== undefined || p.questionToken !== undefined;
  }
  /** False if one is optional and the other isn't, or one is a rest parameter and the other isn't. */
  function parametersHaveEqualSigils(a, b) {
      return ((a.dotDotDotToken !== undefined) === (b.dotDotDotToken !== undefined) &&
          (a.questionToken !== undefined) === (b.questionToken !== undefined));
  }
  function typeParametersAreEqual(a, b) {
      return a.name.text === b.name.text && typesAreEqual(a.constraint, b.constraint);
  }
  function typesAreEqual(a, b) {
      // TODO: Could traverse AST so that formatting differences don't affect this.
      return a === b || (a !== undefined && b !== undefined && a.getText() === b.getText());
  }
  /** Returns the first index where `a` and `b` differ. */
  function getIndexOfFirstDifference(a, b, equal) {
      for (var i = 0; i < a.length && i < b.length; i++) {
          if (!equal(a[i], b[i])) {
              return i;
          }
      }
      return undefined;
  }
  /** Calls `action` for every pair of values in `values`. */
  function forEachPair(values, action) {
      for (var i = 0; i < values.length; i++) {
          for (var j = i + 1; j < values.length; j++) {
              var result = action(values[i], values[j]);
              if (result !== undefined) {
                  return result;
              }
          }
      }
      return undefined;
  }
  function typeText(_a) {
      var type = _a.type;
      return type === undefined ? "any" : type.getText();
  }
  