feat: add constants generation

e2e/anchor/src/generated/constants.rs

@@ -0,0 +1,17 @@
+//! This code was AUTOGENERATED using the codama library.
+//! Please DO NOT EDIT THIS FILE, instead use visitors
+//! to add features, then rerun codama to update it.
+//!
+//! <https://github.com/codama-idl/codama>
+//!
+
+pub const EXTRA_ACCOUNT_METAS: [u8; 19] = [
+    101, 120, 116, 114, 97, 45, 97, 99, 99, 111, 117, 110, 116, 45, 109, 101, 116, 97, 115,
+];
+
+pub const GUARD_V1: [u8; 8] = [103, 117, 97, 114, 100, 95, 118, 49];
+
+pub const WEN_TOKEN_GUARD: [u8; 24] = [
+    119, 101, 110, 95, 116, 111, 107, 101, 110, 95, 116, 114, 97, 110, 115, 102, 101, 114, 95, 103,
+    117, 97, 114, 100,
+];

e2e/anchor/src/generated/mod.rs

@@ -6,6 +6,7 @@
 //!
 
 pub mod accounts;
+pub mod constants;
 pub mod errors;
 pub mod instructions;
 pub mod programs;

public/templates/constantsPage.njk

@@ -0,0 +1,13 @@
+{% extends "layout.njk" %}
+{% import "macros.njk" as macros %}
+
+{% block main %}
+
+{{ imports }}
+
+{% for constant in constants | sort(false, false, 'name') %}
+{{ macros.docblock(constant.docs) }}
+pub const {{ constant.name | snakeCase | upper }}: {{ constant.type }} = {{ constant.value }};
+{% endfor %}
+
+{% endblock %}

public/templates/rootMod.njk

@@ -6,6 +6,9 @@
   {% if accountsToExport.length > 0 %}
     pub mod accounts;
   {% endif %}
+  {% if constantsToExport.length > 0 %}
+    pub mod constants;
+  {% endif %}
   {% if programsToExport.length > 0 %}
     pub mod errors;
   {% endif %}

src/getRenderMapVisitor.ts

@@ -1,6 +1,7 @@
 import { logWarn } from '@codama/errors';
 import {
     getAllAccounts,
+    getAllConstants,
     getAllDefinedTypes,
     getAllInstructionsWithSubs,
     getAllPrograms,
@@ -284,18 +285,44 @@ export function getRenderMapVisitor(options: GetRenderMapOptions = {}) {
                 visitRoot(node, { self }) {
                     const programsToExport = getAllPrograms(node);
                     const accountsToExport = getAllAccounts(node);
+                    const constantsToExport = getAllConstants(node);
                     const instructionsToExport = getAllInstructionsWithSubs(node, {
                         leavesOnly: !renderParentInstructions,
                     });
                     const definedTypesToExport = getAllDefinedTypes(node);
                     const hasAnythingToExport =
                         programsToExport.length > 0 ||
                         accountsToExport.length > 0 ||
+                        constantsToExport.length > 0 ||
                         instructionsToExport.length > 0 ||
                         definedTypesToExport.length > 0;
 
+                    const constants = constantsToExport.map(constant => {
+                        const isBytes = isNode(constant.type, 'bytesTypeNode');
+                        const isString = isNode(constant.type, 'stringTypeNode');
+                        const fixedByteArray =
+                            isNode(constant.type, 'fixedSizeTypeNode') &&
+                            isNode(constant.type.type, 'bytesTypeNode') &&
+                            isNode(constant.value, 'stringValueNode')
+                                ? parseByteArrayConstant(constant.value.string, constant.type.size)
+                                : null;
+                        const typeManifest = isBytes || isString ? null : visit(constant.type, typeManifestVisitor);
+                        const valueManifest = renderValueNode(constant.value, getImportFrom, true);
+
+                        return {
+                            ...constant,
+                            imports: new ImportMap()
+                                .mergeWith(typeManifest?.imports ?? new ImportMap())
+                                .mergeWith(valueManifest.imports),
+                            type: isBytes ? "&'static [u8]" : isString ? "&'static str" : typeManifest!.type,
+                            value: fixedByteArray ?? `${isBytes ? '&' : ''}${valueManifest.render}`,
+                        };
+                    });
+                    const constantsImports = new ImportMap().mergeWith(...constants.map(constant => constant.imports));
+
                     const ctx = {
                         accountsToExport,
+                        constantsToExport,
                         definedTypesToExport,
                         hasAnythingToExport,
                         instructionsToExport,
@@ -309,6 +336,16 @@ export function getRenderMapVisitor(options: GetRenderMapOptions = {}) {
                                 accountsToExport.length > 0
                                     ? { content: render('accountsMod.njk', ctx), imports: new ImportMap() }
                                     : undefined,
+                            ['constants.rs']:
+                                constantsToExport.length > 0
+                                    ? {
+                                          content: render('constantsPage.njk', {
+                                              constants,
+                                              imports: constantsImports.toString(dependencyMap),
+                                          }),
+                                          imports: constantsImports,
+                                      }
+                                    : undefined,
                             ['errors/mod.rs']:
                                 programsToExport.length > 0
                                     ? { content: render('errorsMod.njk', ctx), imports: new ImportMap() }
@@ -340,6 +377,23 @@ export function getRenderMapVisitor(options: GetRenderMapOptions = {}) {
     );
 }
 
+function parseByteArrayConstant(value: string, expectedLength: number): string | null {
+    try {
+        const bytes: unknown = JSON.parse(value);
+        if (
+            !Array.isArray(bytes) ||
+            bytes.length !== expectedLength ||
+            !bytes.every(byte => typeof byte === 'number' && Number.isInteger(byte) && byte >= 0 && byte <= 255)
+        ) {
+            return null;
+        }
+
+        return `[${bytes.join(', ')}]`;
+    } catch {
+        return null;
+    }
+}
+
 function getConflictsForInstructionAccountsAndArgs(instruction: InstructionNode): string[] {
     const allNames = [
         ...(instruction.accounts ?? []).map(account => account.name),

test/constantsPage.test.ts

@@ -0,0 +1,55 @@
+import {
+    bytesTypeNode,
+    bytesValueNode,
+    constantNode,
+    fixedSizeTypeNode,
+    numberTypeNode,
+    numberValueNode,
+    programNode,
+    rootNode,
+    stringValueNode,
+} from '@codama/nodes';
+import { getFromRenderMap } from '@codama/renderers-core';
+import { visit } from '@codama/visitors-core';
+import { test } from 'vitest';
+
+import { getRenderMapVisitor } from '../src';
+import { codeContains } from './_setup';
+
+test('it renders program constants in a top-level constants page', () => {
+    const node = rootNode(
+        programNode({
+            constants: [
+                constantNode('maxOption', numberTypeNode('u8'), numberValueNode(10), ['Maximum options.']),
+                constantNode('seed', bytesTypeNode(), bytesValueNode('utf8', 'seed')),
+            ],
+            name: 'governance',
+            publicKey: 'GovER5Lthms3bLBqWub97yVrQm9WLZ7YgRrxYQYy2f',
+        }),
+    );
+
+    const renderMap = visit(node, getRenderMapVisitor());
+
+    codeContains(getFromRenderMap(renderMap, 'constants.rs').content, [
+        '/// Maximum options.',
+        'pub const MAX_OPTION: u8 = 10;',
+        "pub const SEED: &'static [u8] = &[115, 101, 101, 100];",
+    ]);
+    codeContains(getFromRenderMap(renderMap, 'mod.rs').content, 'pub mod constants;');
+});
+
+test('it renders JSON byte arrays from Anchor constants as fixed byte arrays', () => {
+    const node = rootNode(
+        programNode({
+            constants: [
+                constantNode('guardV1', fixedSizeTypeNode(bytesTypeNode(), 3), stringValueNode('[103, 117, 97]')),
+            ],
+            name: 'tokenGuard',
+            publicKey: 'TokenkegQfeZyiNwAJbNbGKPFXCWuBvf9Ss623VQ5DA',
+        }),
+    );
+
+    const renderMap = visit(node, getRenderMapVisitor());
+
+    codeContains(getFromRenderMap(renderMap, 'constants.rs').content, 'pub const GUARD_V1: [u8; 3] = [103, 117, 97];');
+});