Skip to content

Commit d46b424

Browse files
sbc100sbc100
authored
Simplify JS preprocessor so it always takes a filename. NFC (emscripten-core#18522)
I noticed this nice simplification while working on emscripten-core#18520
1 parent cfc4540 commit d46b424

4 files changed

Lines changed: 15 additions & 18 deletions

File tree

‎src/jsifier.js‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -455,7 +455,7 @@ function ${name}(${args}) {
455455

456456
function includeFile(fileName) {
457457
print(`// include: ${fileName}`);
458-
print(processMacros(preprocess(read(fileName), fileName)));
458+
print(processMacros(preprocess(fileName)));
459459
print(`// end include: ${fileName}`);
460460
}
461461

‎src/modules.js‎

Lines changed: 3 additions & 3 deletions
Original file line numberDiff line numberDiff line change
@@ -193,7 +193,6 @@ global.LibraryManager = {
193193
printErr('processing system library: ' + filename);
194194
}
195195
}
196-
const src = read(filename);
197196
let origLibrary = undefined;
198197
let processed = undefined;
199198
// When we parse user libraries also set `__user` attribute
@@ -211,15 +210,16 @@ global.LibraryManager = {
211210
});
212211
}
213212
try {
214-
processed = processMacros(preprocess(src, filename));
213+
processed = processMacros(preprocess(filename));
215214
vm.runInThisContext(processed, { filename: filename.replace(/\.\w+$/, '.preprocessed$&') });
216215
} catch (e) {
217216
error(`failure to execute js library "${filename}":`);
218217
if (VERBOSE) {
218+
const orig = read(filename);
219219
if (processed) {
220220
error(`preprocessed source (you can run a js engine on this to get a clearer error message sometimes):\n=============\n${processed}\n=============`);
221221
} else {
222-
error(`original source:\n=============\n${src}\n=============`);
222+
error(`original source:\n=============\n${orig}\n=============`);
223223
}
224224
} else {
225225
error('use -sVERBOSE to see more details');

‎src/parseTools.js‎

Lines changed: 10 additions & 12 deletions
Original file line numberDiff line numberDiff line change
@@ -34,9 +34,8 @@ function processMacros(text) {
3434
// Simple #if/else/endif preprocessing for a file. Checks if the
3535
// ident checked is true in our global.
3636
// Also handles #include x.js (similar to C #include <file>)
37-
// Param filenameHint can be passed as a description to identify the file that is being processed, used
38-
// to locate errors for reporting and for html files to stop expansion between <style> and </style>.
39-
function preprocess(text, filenameHint) {
37+
function preprocess(filename) {
38+
let text = read(filename);
4039
if (EXPORT_ES6 && USE_ES6_IMPORT_META) {
4140
// `eval`, Terser and Closure don't support module syntax; to allow it,
4241
// we need to temporarily replace `import.meta` and `await import` usages
@@ -56,8 +55,8 @@ function preprocess(text, filenameHint) {
5655
const showStack = [];
5756
const showCurrentLine = () => showStack.every((x) => x == SHOW);
5857

59-
currentlyParsedFilename = filenameHint;
60-
const fileExt = (filenameHint) ? filenameHint.split('.').pop().toLowerCase() : '';
58+
currentlyParsedFilename = filename;
59+
const fileExt = filename.split('.').pop().toLowerCase();
6160
const isHtml = (fileExt === 'html' || fileExt === 'htm') ? true : false;
6261
let inStyle = false;
6362
const lines = text.split('\n');
@@ -94,16 +93,15 @@ function preprocess(text, filenameHint) {
9493
}
9594
}
9695
const after = trimmed.substring(trimmed.indexOf(' '));
97-
const truthy = !!vm.runInThisContext(after, { filename: filenameHint, lineOffset: i, columnOffset: line.indexOf(after) });
96+
const truthy = !!vm.runInThisContext(after, { filename, lineOffset: i, columnOffset: line.indexOf(after) });
9897
showStack.push(truthy ? SHOW : IGNORE);
9998
} else if (first === '#include') {
10099
if (showCurrentLine()) {
101100
let filename = line.substr(line.indexOf(' ') + 1);
102101
if (filename.startsWith('"')) {
103102
filename = filename.substr(1, filename.length - 2);
104103
}
105-
const included = read(filename);
106-
const result = preprocess(included, filename);
104+
const result = preprocess(filename);
107105
if (result) {
108106
ret += `// include: ${filename}\n`;
109107
ret += result;
@@ -123,14 +121,14 @@ function preprocess(text, filenameHint) {
123121
showStack.pop();
124122
} else if (first === '#warning') {
125123
if (showCurrentLine()) {
126-
printErr(`${filenameHint}:${i + 1}: #warning ${trimmed.substring(trimmed.indexOf(' ')).trim()}`);
124+
printErr(`${filename}:${i + 1}: #warning ${trimmed.substring(trimmed.indexOf(' ')).trim()}`);
127125
}
128126
} else if (first === '#error') {
129127
if (showCurrentLine()) {
130-
error(`${filenameHint}:${i + 1}: #error ${trimmed.substring(trimmed.indexOf(' ')).trim()}`);
128+
error(`${filename}:${i + 1}: #error ${trimmed.substring(trimmed.indexOf(' ')).trim()}`);
131129
}
132130
} else {
133-
throw new Error(`${filenameHint}:${i + 1}: Unknown preprocessor directive ${first}`);
131+
throw new Error(`${filename}:${i + 1}: Unknown preprocessor directive ${first}`);
134132
}
135133
} else {
136134
if (showCurrentLine()) {
@@ -152,7 +150,7 @@ function preprocess(text, filenameHint) {
152150
}
153151
}
154152
}
155-
assert(showStack.length == 0, `preprocessing error in file ${filenameHint}, \
153+
assert(showStack.length == 0, `preprocessing error in file ${filename}, \
156154
no matching #endif found (${showStack.length$}' unmatched preprocessing directives on stack)`);
157155
return ret;
158156
} finally {

‎tools/preprocessor.js‎

Lines changed: 1 addition & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -59,7 +59,6 @@ load('utility.js');
5959
load('modules.js');
6060
load('parseTools.js');
6161

62-
const fromHTML = read(shellFile);
63-
const toHTML = expandMacros ? processMacros(preprocess(fromHTML, shellFile)) : preprocess(fromHTML, shellFile);
62+
const toHTML = expandMacros ? processMacros(preprocess(shellFile)) : preprocess(shellFile);
6463

6564
print(toHTML);

0 commit comments

Comments
 (0)