delta/go-git.git/src/database, branch dev.go2go

database/sql: close driver.Connector if it implements io.Closer

2021-02-25T19:34:27+00:00

This change allows driver implementations to manage resources in
driver.Connector, e.g. to share the same underlying database handle
between multiple connections. That is, it allows embedded databases
with in-memory backends like SQLite and Genji to safely release the
resources once the sql.DB is closed.

This makes it possible to address oddities with in-memory stores in
SQLite and Genji drivers without introducing too much complexity in
the driver implementations.

See also:
- https://github.com/mattn/go-sqlite3/issues/204
- https://github.com/mattn/go-sqlite3/issues/511
- https://github.com/genjidb/genji/issues/210

Fixes #41790

Change-Id: Idbd19763134438ed38288b9d44f16608e4e97fd7
GitHub-Last-Rev: 962c785dfb3bb6ad98b2216bcedd84ba383fe872
GitHub-Pull-Request: golang/go#41710
Reviewed-on: https://go-review.googlesource.com/c/go/+/258360
Reviewed-by: Emmanuel Odeke 
Reviewed-by: Daniel Theophanes 
Trust: Emmanuel Odeke 
Run-TryBot: Emmanuel Odeke 
TryBot-Result: Go Bot

database: remove race in TestTxContextWait

2021-02-24T14:10:04+00:00

This test contained a data race.
On line 437, db.BeginTx starts a goroutine that runs tx.awaitDone,
which reads tx.keepConnOnRollback.
On line 445, the test writes to tx.keepConnOnRollback.
tx.awaitDone waits on ctx, but because ctx is timeout-based,
there's no ordering guarantee between the write and the read.

The race detector never caught this before
because the context package implementation of Done
contained enough synchronization to make it safe.
That synchronization is not package of the context API or guarantees,
and the first several releases it was not present.
Another commit soon will remove that synchronization,
exposing the latent data race.

To fix the race, emulate a time-based context
using an explicit cancellation-based context.
This gives us enough control to avoid the race.

Change-Id: I103fe9b987b1d4c02e7a20ac3c22a682652128b6
Reviewed-on: https://go-review.googlesource.com/c/go/+/288493
Trust: Josh Bleecher Snyder 
Run-TryBot: Josh Bleecher Snyder 
TryBot-Result: Go Bot 
Reviewed-by: Daniel Theophanes

database/sql: fix typo in comment

2020-12-10T18:23:15+00:00

Fixes #43116

Change-Id: Ib04fab6ae03f322aa1508ec00523f628d891247a
GitHub-Last-Rev: 0a86e665b2c320e0b2aef75ee53bd7281b19b013
GitHub-Pull-Request: golang/go#43122
Reviewed-on: https://go-review.googlesource.com/c/go/+/276992
Reviewed-by: Ian Lance Taylor 
Reviewed-by: Daniel Theophanes

database/sql, runtime: correct *.Fatal inside goroutines in tests

2020-10-31T20:30:19+00:00

Found by go vet pass "testinggoroutines".

Change-Id: I6360af2079617b7aa62dcb9bd7254578ca5d1c1d
Reviewed-on: https://go-review.googlesource.com/c/go/+/235527
Run-TryBot: Emmanuel Odeke 
Reviewed-by: Ian Lance Taylor 
Trust: Emmanuel Odeke

database/sql: fix TestTxStmtDeadlock test

2020-10-29T00:19:20+00:00

Drop error check because errors can be
not only ErrTxDone for tx stmt executions,
and the purpose of the test is just reproducing
deadlock.

Fixes #42259

Change-Id: I9e7105ada1403ec7064dcc1c3385b36893a1c195
Reviewed-on: https://go-review.googlesource.com/c/go/+/266097
Reviewed-by: Daniel Theophanes 
Trust: Emmanuel Odeke 
Run-TryBot: Emmanuel Odeke 
TryBot-Result: Go Bot

database/sql: fix tx stmt deadlock when rollback

2020-10-28T16:55:17+00:00

Tx acquires tx.closemu W-lock and then acquires stmt.closemu.W-lock
to fully close the transaction and associated prepared statement.
Stmt query and execution run in reverse ways - acquires
stmt.closemu.R-lock and then acquires tx.closemu.R-lock to grab tx
connection, which may cause deadlock.

Prevent the lock is held around tx.closePrepared to ensure no
deadlock happens.

Fixes #40985

Change-Id: If53909822b87bce11861a6e3035ecb9476d2cd17
Reviewed-on: https://go-review.googlesource.com/c/go/+/250178
Run-TryBot: Emmanuel Odeke 
TryBot-Result: Go Bot 
Reviewed-by: Daniel Theophanes 
Trust: Emmanuel Odeke

database/sql: fix comment on DB.stop()

2020-10-27T15:12:12+00:00

Previously, 2 goroutines were created in OpenDB and a comment in the DB.close() field indicated that they were canceled. Later, session Resetter () was removed, but the comment remained the same. This commit just fixes this message

Change-Id: Ie81026f51d7770e9cf8004818154021f626fb2e8
GitHub-Last-Rev: 38b338a0d1cd713d71fa547aa842d395e6d75484
GitHub-Pull-Request: golang/go#42191
Reviewed-on: https://go-review.googlesource.com/c/go/+/264838
Reviewed-by: Daniel Theophanes 
Reviewed-by: Brad Fitzpatrick 
Trust: Brad Fitzpatrick

database/sql: shortestIdleTimeLocked correct min comparison

2020-08-29T09:20:35+00:00

When zero or less, maxIdleTime and maxLifetime means unlimited.
Helper function shortestIdleTimeLocked must not return the
minimum of the two until both are verified to be greater
then zero.

Fixes #40841

Change-Id: I1130332baf4ad259cd90c10f4221f5def8510655
Reviewed-on: https://go-review.googlesource.com/c/go/+/248817
Reviewed-by: Daniel Theophanes

database/sql: make Rows.Scan properly wrap underlying errors

2020-08-14T17:45:39+00:00

The prior implementation used the format verb %v which unfortunately
improperly wrapped any underlying scanner errors, and we couldn't use
errors.Is nor errors.As. This change fixes that by using the %w verb.

Added a unit to ensure that both error sub string matching works, but
also that errors.Is works as expected.

Fixes #38099

Change-Id: Iea667041dd8081d961246f77f2542330417292dc
Reviewed-on: https://go-review.googlesource.com/c/go/+/248337
Reviewed-by: Emmanuel Odeke 
Reviewed-by: Daniel Theophanes 
Run-TryBot: Emmanuel Odeke 
TryBot-Result: Gobot Gobot

database/sql/driver: use correct method name "Connect" in DriverContext docs

2020-05-30T03:20:54+00:00

Change-Id: I755fedebb1f8f4d3f27b2b3f8626bca03bd36c88
GitHub-Last-Rev: 4a123572d55ad3b0104d3e6501eef5b2f37af4cd
GitHub-Pull-Request: golang/go#39305
Reviewed-on: https://go-review.googlesource.com/c/go/+/235518
Reviewed-by: Emmanuel Odeke 
Reviewed-by: Daniel Theophanes