Enabling SQLite FTS5 module by default.

[serpulga]

Compiled using EMSCRIPTEN 1.37.9.

Tests:

$ ./test/run.sh 
Testing ./test/test_blob.js...	writeStringToMemory is deprecated and should not be called! Use stringToUTF8() instead!
Passed.
Testing ./test/test_database.js...	writeStringToMemory is deprecated and should not be called! Use stringToUTF8() instead!
Passed.
Testing ./test/test_errors.js...	writeStringToMemory is deprecated and should not be called! Use stringToUTF8() instead!
Passed.
Testing ./test/test_extension_functions.js...	writeStringToMemory is deprecated and should not be called! Use stringToUTF8() instead!
Passed.
Testing ./test/test_functions.js...	writeStringToMemory is deprecated and should not be called! Use stringToUTF8() instead!
Passed.
Testing ./test/test_issue128.js...	writeStringToMemory is deprecated and should not be called! Use stringToUTF8() instead!
Passed.
Testing ./test/test_issue55.js...	Passed.
Testing ./test/test_issue73.js...	writeStringToMemory is deprecated and should not be called! Use stringToUTF8() instead!
Passed.
Testing ./test/test_issue76.js...	Passed.
Testing ./test/test_node_file.js...	writeStringToMemory is deprecated and should not be called! Use stringToUTF8() instead!
Passed.
Testing ./test/test_statement.js...	writeStringToMemory is deprecated and should not be called! Use stringToUTF8() instead!
Passed.
Testing ./test/test_transactions.js...	writeStringToMemory is deprecated and should not be called! Use stringToUTF8() instead!
Passed.
Testing ./test/test_worker.js...	writeStringToMemory is deprecated and should not be called! Use stringToUTF8() instead!

assert.js:90
  throw new assert.AssertionError({
  ^
AssertionError: Reading BLOB
    at Worker.worker.onmessage (/Users/serpulga/Documents/src/sql.js/test/test_worker.js:23:14)
    at ChildProcess.<anonymous> (/Users/serpulga/Documents/src/sql.js/node_modules/workerjs/index.js:25:38)
    at emitTwo (events.js:87:13)
    at ChildProcess.emit (events.js:172:7)
    at handleMessage (internal/child_process.js:695:10)
    at Pipe.channel.onread (internal/child_process.js:440:11)
Fail!\e[0m
Warning\e[0m : 12 tests passed out of 13

Same error I get on master [6dc4ac5].

[petermolnar]

+1 for this; if the FTS5 engine is on, that'd allow search indexes created by other languages to be used in JS in the browser.

[lovasoa]

sql.js is already quite a huge dependency to have. I don't think adding other modules by default is a good idea.

But compiling different versions for different needs is a good idea.

[3CE8D2BAC65BDD6AA9]

I believe I am able to have FTS5 running. Here are the procedures:

1. modify Makefile by adding "-DSQLITE_ENABLE_FTS5" in the CFLAGS line. So, the complete CFLAGS line will become CFLAGS=-O2 -DSQLITE_OMIT_LOAD_EXTENSION -DSQLITE_DISABLE_LFS -DLONGDOUBLE_TYPE=double -DSQLITE_THREADSAFE=0 -DSQLITE_ENABLE_FTS3 -DSQLITE_ENABLE_FTS3_PARENTHESIS -DSQLITE_ENABLE_FTS5
2. make
3. A few .js files will be created at the js directory. I tested worker.sql.js only so far
4. In order to test it, I cloned http://kripken.github.io/sql.js/GUI/ to my server and then delete the line <script src="codemirror/mode/sql/sql.js"></script>
5. Modify gui.js to point to my own worker.sql.js at this line <a href="https://github.com/kripken/sql.js"> to var worker = new Worker("worker.sql.js");
6. run the gui page
7. I typed the commands from http://www.sqlitetutorial.net/sqlite-full-text-search/ into the textarea box. All FTS5 commands work perfectly.

In the next few weeks, I will try to test the performance of FTS5 by adding thousands of documents.

[serpulga]

@3CE8D2BAC65BDD6AA9 Thank you for posting the steps. I was also able to run FTS5 but this pull request was to enable it by default inside sql.js; but since I agree with @lovasoa (we shouldn't add modules that most people won't use) I didn't even try to fix the failing unit tests.

[brodybits]

Why change the SQLITE_THREADSAFE default setting? Was this intended?

[3CE8D2BAC65BDD6AA9]

I noticed the same thing but no clue why there is such a different.

[dinedal]

I am open to the idea of making such compile time extensions into different versions of sql.js (such as memory-growth, debug, etc).

Would that be a good solution here? Can we expect future extensions to pass the standard test suite? Would a standard procedure for adding such extensions help in the future?

[jrocha]

Would be nice to have an extra flavor with FTS5 enabled.

[jerefrer]

I also wonder if that would be a good idea to include it by default, but I definitely would love to have a ready-made version with FTS5 enabled.