delphi13-preprocessor

Standalone Delphi 13 preprocessor — resolves {$IFDEF} / {$IF} / {$ELSE} / {$ENDIF} chains, {$DEFINE} / {$UNDEF}, {$I X.inc} includes, and numeric directives. Produces preprocessor-resolved text suitable for tree-sitter-delphi13-pure or any other consumer that prefers flat source.

Pairs with the pure tree-sitter sub-grammar to reach 99.33% parse rate on real-world Delphi 13 corpora.

Install

npm install delphi13-preprocessor

Library usage

const fs = require('fs');
const { preprocess } = require('delphi13-preprocessor');

const raw = fs.readFileSync('MyUnit.pas', 'utf8');

const { text, defines } = preprocess(raw, {
  defines: ['MSWINDOWS', 'WIN64', 'CPU64BITS', 'UNICODE',
            'COMPILER_VERSION_37', 'VER370',
            'SUPPORTS_GENERICS', 'SUPPORTS_INLINE',
            'ASSEMBLER'],
  numericDefines: {
    CompilerVersion: 37,
    RTLVersion: 37,
  },
  baseDir: 'C:/MyProject',     // for {$I X.inc} resolution (same-dir only)
  includeMode: 'expand',       // 'expand' (default) | 'defines-only' | 'off'
});

// Returns `{ text, defines }`:
//   text    — the active-branch source with inactive branches (and directives)
//             replaced by whitespace, preserving line AND byte offsets so
//             tree-sitter positions map 1:1 back to the ORIGINAL file.
//   defines — the final define set (Array) after all {$DEFINE}/{$UNDEF}.

// `includeMode` controls {$I X.inc} handling:
//   'expand'       — splice the resolved .inc body into the output (default).
//                    Shifts offsets after the include point.
//   'defines-only' — apply the .inc's {$DEFINE}/{$UNDEF} to the parent (so a
//                    later {$IFDEF X} in the parent resolves correctly) but do
//                    NOT splice the body. Keeps output 1:1 with input, and does
//                    not duplicate .inc symbols for consumers that index .inc
//                    files separately.
//   'off'          — blank the {$I} directive, ignore its defines. 1:1 offsets.

CLI

node node_modules/delphi13-preprocessor/cli.js path/to/file.pas [--defines defines.json]

Emits preprocessed pure-Pascal text to stdout.

Supported directives

• Conditional: {$IFDEF} / {$IFNDEF} / {$IF expr} / {$ELSEIF expr} / {$ELSE} / {$ENDIF} / {$IFEND}
• Define management: {$DEFINE Name}, {$UNDEF Name}
• Includes: {$I X.inc} and {$INCLUDE X.inc} (same-directory resolution)
• Expression evaluation in {$IF}:
  • defined(X), not defined(X)
  • Boolean and / or / not
  • Numeric comparison: CompilerVersion >= 21.0, RTLVersion < 31
  • Parenthesized sub-expressions

What it does NOT do

• {$IF declared(SymName)} always returns false. Implementing this would require a lightweight symbol pre-scan (TYPE/CONST/VAR/FUNCTION declarations in the same unit). On the TODO list.
• Cross-directory {$I} search paths. Currently the include file must live in the same directory as the file being preprocessed. Search-path support is on the TODO list.
• {$INLINE} / {$EXTERNALSYM} / {$WARN} and other purely-compiler directives — these are passed through as-is (consumers see them in extras).

Per-project defines profiles

For real-world parsing, you often need project-specific defines to pick the right IFDEF branches. The orchestrator in the parent repo uses path-based regex profiles for EurekaLog, AsyncPro, FireDAC, fibplus, and Indy. Example:

const PATH_DEFINES = [
  { re: /EurekaLog/i, defs: ['EUREKALOG', 'USE_NAMESPACES', 'COMPILER37', /* ... */] },
  { re: /AsyncPro/i, defs: ['PRNDRV', 'APAX', 'Ver130', 'Ver140', 'Ver150'] },
  { re: /FireDAC/i, defs: ['FireDAC_64', 'FireDAC_SQLITE_EXTERNAL'] },
];

See tools/parse-corpus-orchestrated.js in the parent repo for the full reference set.

License

MIT.