hvolt-ide

An IDE that runs on the HarmonyOS device itself. It edits ArkTS, builds and installs the project with hvolt through a native bridge, and carries a chat loop that can call those same build tools.

No desktop IDE, no DevEco Studio, no host-side file sync: the phone is the workstation.

What it does

• Editor — ArkTS sources with syntax highlighting, tabs, line numbers, word wrap and an embedded code editor. Language support (completion, diagnostics) comes from the hvolt LSP over the same bridge.
• Build — build, sign, push and start run inside the app. Output, signing state and device link are shown in the workbench.
• Chat — a streaming loop against any OpenAI-compatible endpoint, with tool calls into the build chain, file system and device shell. Replies render markdown: tables, token-coloured code, and mermaid diagrams.
• Layout — three breakpoints (compact / medium / expanded) and landscape. The toolbar, activity bar, panes and dock rearrange rather than scale.

How it is put together

app/src/pages/model/      session state: project, editor, device link, build steps
app/src/pages/view/       the surfaces: panes, editor area, chat panel, settings, dock
app/src/pages/harness/    the chat loop: client, stream decoding, tools, MCP registry
app/src/pages/model/*.ts   pure logic with tests: markdown, stream, commands, format, completion, urls
test/                      node --test suites and the import-graph check

Device-side capability comes from libhvolt.so, a native library that exposes hvolt's build, device and stream functions to ArkTS. ArkTS compilation on the device uses the SDK's own es2abc.

Building

Requires hvolt (see its repository for install) and a HarmonyOS SDK.

Two kinds of files are not in this repository and have to be provided locally:

Path	What it is	Where it comes from
app/src/libs/arm64-v8a/libes2abc.so	the device-side ArkTS compiler	the HarmonyOS SDK's ets/build-tools, cross-built for arm64
app/resources/rawfile/sdk/	API declarations the editor offers completions from	$SDK/<version>/ets/api, plus index.tsv

Both are SDK distribution and would put a 61 MB binary and several hundred .d.ts files into the history, so they are ignored. Without them the app builds and runs, but the on-device compiler and completion are unavailable.

Signing material (app/signing/) is likewise ignored: it holds the keystore. With it absent, hvolt build produces an unsigned package. The passwords in app/hvolt.toml are inert without the keystore they belong to.

cd app
hvolt build            # → build/entry-unsigned.hap
hvolt push <device>
hvolt start xyz.sudofree.hvolt.ide

Tests

node --test test/            # 96 cases: markdown, stream decoding, commands, format, completion, urls
python3 test/check-imports.py

check-imports.py exists because the build chain does not verify that a named import is exported by its source module; a symbol moved between files compiles cleanly and crashes the app at startup. hvolt runs the same check before compiling.

Limitations

Native modules are not built on the device. The build chain covers ArkTS only. A project that declares a C++/NAPI module — a type = "native" dependency, or cpp/CMakeLists.txt under a member — expects a host-side toolchain (clang, cmake, the NDK) that the device does not carry, and the build reports the failure rather than cross-compiling it. Projects that need native code still have to be built on a host and installed from there.

No automated UI tests. The .ts modules under test/ cover parsing and formatting; the surfaces themselves are verified by running them on a device.