Create queries for only inherited contract methods in codegen generated watchers (#371)

* Codegen create queries only for inherited contracts

* Refactor recursive method to filter inherited contracts

* Comment code and refactor

---------

Co-authored-by: Dhruv Srivastava <dhruvdhs.ds@gmail.com>

packages/codegen/src/generate-code.ts

@@ -14,6 +14,7 @@ import os from 'os';
 
 import { flatten } from '@poanet/solidity-flattener';
 import { parse, visit } from '@solidity-parser/parser';
+import { ASTNode } from '@solidity-parser/parser/dist/src/ast-types';
 import { KIND_ACTIVE, KIND_LAZY } from '@cerc-io/util';
 
 import { MODE_ETH_CALL, MODE_STORAGE, MODE_ALL, MODE_NONE, DEFAULT_PORT } from './utils/constants';
@@ -38,7 +39,7 @@ import { getSubgraphConfig } from './utils/subgraph';
 import { exportIndexBlock } from './index-block';
 import { exportSubscriber } from './subscriber';
 import { exportReset } from './reset';
-import { writeFileToStream } from './utils/helpers';
+import { filterInheritedContractNodes, writeFileToStream } from './utils/helpers';
 
 const ASSET_DIR = path.resolve(__dirname, 'assets');
 
@@ -146,8 +147,14 @@ function parseAndVisit (visitor: Visitor, contracts: any[], mode: string) {
       // Get the abstract syntax tree for the flattened contract.
       const ast = parse(contract.contractString);
 
-      // Filter out library nodes.
-      ast.children = ast.children.filter(child => !(child.type === 'ContractDefinition' && child.kind === 'library'));
+      const contractNode = ast.children.find((node: ASTNode) =>
+        node.type === 'ContractDefinition' &&
+        node.name === contract.contractName
+      );
+
+      assert(contractNode);
+      const nodes = filterInheritedContractNodes(ast, [contractNode]);
+      ast.children = Array.from(nodes).concat(contractNode);
 
       visit(ast, {
         StateVariableDeclaration: stateVariableDeclarationVisitor,

packages/codegen/src/utils/helpers.ts

@@ -4,7 +4,8 @@
 
 import fs from 'fs';
 import { Writable } from 'stream';
-import { TypeName } from '@solidity-parser/parser/dist/src/ast-types';
+
+import { TypeName, ASTNode, InheritanceSpecifier, SourceUnit } from '@solidity-parser/parser/dist/src/ast-types';
 
 export const isArrayType = (typeName: TypeName): boolean => (typeName.type === 'ArrayTypeName');
 
@@ -22,3 +23,38 @@ export function writeFileToStream (pathToFile: string, outStream: Writable): voi
   const fileStream = fs.createReadStream(pathToFile);
   fileStream.pipe(outStream);
 }
+
+/**
+ * Get inherited contracts for array of contractNodes
+ * @param ast
+ * @param contractNodes
+ */
+export function filterInheritedContractNodes (ast: SourceUnit, contractNodes: ASTNode[]): Set<ASTNode> {
+  const resultSet: Set<ASTNode> = new Set();
+
+  contractNodes.forEach((node: ASTNode) => {
+    if (node.type !== 'ContractDefinition') {
+      return;
+    }
+
+    // Filter out library nodes
+    if (node.kind === 'library') {
+      return;
+    }
+
+    const inheritedContracts = ast.children.filter((childNode: ASTNode) =>
+      node.baseContracts.some((baseContract: InheritanceSpecifier) =>
+        childNode.type === 'ContractDefinition' && baseContract.baseName.namePath === childNode.name
+      )
+    );
+
+    // Add inherited contracts to result set
+    inheritedContracts.forEach((node: ASTNode) => resultSet.add(node));
+    // Get parent inherited contracts
+    const parentInheritedNodes = filterInheritedContractNodes(ast, inheritedContracts);
+    // Add parent inherited contract nodes in result set
+    parentInheritedNodes.forEach((node: ASTNode) => resultSet.add(node));
+  });
+
+  return resultSet;
+}