[SPARK-23435][SPARKR][TESTS] Update testthat to >= 2.0.0

### What changes were proposed in this pull request?

- Update `testthat` to >= 2.0.0
- Replace of `testthat:::run_tests` with `testthat:::test_package_dir`
- Add trivial assertions for tests, without any expectations, to avoid skipping.
- Update related docs.

### Why are the changes needed?

`testthat` version has been frozen by [SPARK-22817](https://issues.apache.org/jira/browse/SPARK-22817) / #20003, but 1.0.2 is pretty old, and we shouldn't keep things in this state forever.

### Does this PR introduce any user-facing change?

No.

### How was this patch tested?

- Existing CI pipeline:
     - Windows build on AppVeyor, R 3.6.2, testthtat 2.3.1
     - Linux build on Jenkins, R 3.1.x, testthat 1.0.2

- Additional builds with thesthat 2.3.1  using [sparkr-build-sandbox](https://github.com/zero323/sparkr-build-sandbox) on c7ed64a

   R 3.4.4  (image digest ec9032f8cf98)
   ```
   docker pull zero323/sparkr-build-sandbox:3.4.4
   docker run zero323/sparkr-build-sandbox:3.4.4 zero323 --branch SPARK-23435 --commit c7ed64a --public-key https://keybase.io/zero323/pgp_keys.asc
    ```
    3.5.3 (image digest 0b1759ee4d1d)

    ```
    docker pull zero323/sparkr-build-sandbox:3.5.3
    docker run zero323/sparkr-build-sandbox:3.5.3 zero323 --branch SPARK-23435 --commit
    c7ed64a --public-key https://keybase.io/zero323/pgp_keys.asc
    ```

   and 3.6.2 (image digest 6594c8ceb72f)
    ```
   docker pull zero323/sparkr-build-sandbox:3.6.2
   docker run zero323/sparkr-build-sandbox:3.6.2 zero323 --branch SPARK-23435 --commit c7ed64a --public-key https://keybase.io/zero323/pgp_keys.asc
   ````

   Corresponding [asciicast](https://asciinema.org/) are available as 10.5281/zenodo.3629431

     [![DOI](https://zenodo.org/badge/DOI/10.5281/zenodo.3629431.svg)](https://doi.org/10.5281/zenodo.3629431)

   (a bit to large to burden asciinema.org, but can run locally via `asciinema play`).

----------------------------

Continued from #27328

Closes #27359 from zero323/SPARK-23435.

Authored-by: zero323 <mszymkiewicz@gmail.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>

R/pkg/tests/fulltests/test_context.R

@@ -84,6 +84,7 @@ test_that("rdd GC across sparkR.stop", {
   countRDD(rdd3)
   countRDD(rdd4)
   sparkR.session.stop()
+  expect_true(TRUE)
 })
 
 test_that("job group functions can be called", {
@@ -93,6 +94,7 @@ test_that("job group functions can be called", {
   clearJobGroup()
 
   sparkR.session.stop()
+  expect_true(TRUE)
 })
 
 test_that("job description and local properties can be set and got", {
@@ -131,6 +133,7 @@ test_that("utility function can be called", {
   sparkR.sparkContext(master = sparkRTestMaster)
   setLogLevel("ERROR")
   sparkR.session.stop()
+  expect_true(TRUE)
 })
 
 test_that("getClientModeSparkSubmitOpts() returns spark-submit args from whitelist", {
@@ -234,4 +237,5 @@ test_that("SPARK-25234: parallelize should not have integer overflow", {
   # 47000 * 47000 exceeds integer range
   parallelize(sc, 1:47000, 47000)
   sparkR.session.stop()
+  expect_true(TRUE)
 })

R/pkg/tests/fulltests/test_includePackage.R

@@ -39,6 +39,7 @@ test_that("include inside function", {
     data <- lapplyPartition(rdd, generateData)
     actual <- collectRDD(data)
   }
+  expect_true(TRUE)
 })
 
 test_that("use include package", {
@@ -55,6 +56,7 @@ test_that("use include package", {
     data <- lapplyPartition(rdd, generateData)
     actual <- collectRDD(data)
   }
+  expect_true(TRUE)
 })
 
 sparkR.session.stop()

R/pkg/tests/fulltests/test_sparkSQL.R

@@ -1382,6 +1382,7 @@ test_that("column operators", {
   c5 <- c2 ^ c3 ^ c4
   c6 <- c2 %<=>% c3
   c7 <- !c6
+  expect_true(TRUE)
 })
 
 test_that("column functions", {

R/pkg/tests/fulltests/test_textFile.R

@@ -75,6 +75,7 @@ test_that("several transformations on RDD created by textFile()", {
   collectRDD(rdd)
 
   unlink(fileName)
+  expect_true(TRUE)
 })
 
 test_that("textFile() followed by a saveAsTextFile() returns the same content", {

R/pkg/tests/run-all.R

@@ -20,7 +20,6 @@ library(SparkR)
 
 # SPARK-25572
 if (identical(Sys.getenv("NOT_CRAN"), "true")) {
-
   # Turn all warnings into errors
   options("warn" = 2)
 
@@ -60,11 +59,23 @@ if (identical(Sys.getenv("NOT_CRAN"), "true")) {
   if (identical(Sys.getenv("NOT_CRAN"), "true")) {
     # set random seed for predictable results. mostly for base's sample() in tree and classification
     set.seed(42)
-    # for testthat 1.0.2 later, change reporter from "summary" to default_reporter()
-    testthat:::run_tests("SparkR",
-                         file.path(sparkRDir, "pkg", "tests", "fulltests"),
-                         NULL,
-                         "summary")
+
+    # TODO (SPARK-30663) To be removed once testthat 1.x is removed from all builds
+    if (grepl("^1\\..*", packageVersion("testthat"))) {
+      # testthat 1.x
+      test_runner <- testthat:::run_tests
+      reporter <- "summary"
+
+    } else {
+      # testthat >= 2.0.0
+      test_runner <- testthat:::test_package_dir
+      reporter <- testthat::default_reporter()
+    }
+
+    test_runner("SparkR",
+                file.path(sparkRDir, "pkg", "tests", "fulltests"),
+                NULL,
+                reporter)
   }
 
   SparkR:::uninstallDownloadedSpark()

appveyor.yml

@@ -43,11 +43,7 @@ install:
   - ps: .\dev\appveyor-install-dependencies.ps1
   # Required package for R unit tests
   - cmd: R -e "install.packages(c('knitr', 'rmarkdown', 'e1071', 'survival', 'arrow'), repos='https://cloud.r-project.org/')"
-  # Here, we use the fixed version of testthat. For more details, please see SPARK-22817.
-  # As of devtools 2.1.0, it requires testthat higher then 2.1.1 as a dependency. SparkR test requires testthat 1.0.2.
-  # Therefore, we don't use devtools but installs it directly from the archive including its dependencies.
-  - cmd: R -e "install.packages(c('crayon', 'praise', 'R6'), repos='https://cloud.r-project.org/')"
-  - cmd: R -e "install.packages('https://cloud.r-project.org/src/contrib/Archive/testthat/testthat_1.0.2.tar.gz', repos=NULL, type='source')"
+  - cmd: R -e "install.packages(c('crayon', 'praise', 'R6', 'testthat'), repos='https://cloud.r-project.org/')"
   - cmd: R -e "packageVersion('knitr'); packageVersion('rmarkdown'); packageVersion('testthat'); packageVersion('e1071'); packageVersion('survival'); packageVersion('arrow')"
 
 build_script:

docs/README.md

@@ -6,9 +6,9 @@ license: |
   The ASF licenses this file to You under the Apache License, Version 2.0
   (the "License"); you may not use this file except in compliance with
   the License.  You may obtain a copy of the License at
- 
+
      http://www.apache.org/licenses/LICENSE-2.0
- 
+
   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
@@ -39,9 +39,8 @@ installed. Also install the following libraries:
 $ sudo gem install jekyll jekyll-redirect-from rouge
 # Following is needed only for generating API docs
 $ sudo pip install sphinx pypandoc mkdocs
-$ sudo Rscript -e 'install.packages(c("knitr", "devtools", "rmarkdown"), repos="https://cloud.r-project.org/")'
+$ sudo Rscript -e 'install.packages(c("knitr", "devtools", "testthat", "rmarkdown"), repos="https://cloud.r-project.org/")'
 $ sudo Rscript -e 'devtools::install_version("roxygen2", version = "5.0.1", repos="https://cloud.r-project.org/")'
-$ sudo Rscript -e 'devtools::install_version("testthat", version = "1.0.2", repos="https://cloud.r-project.org/")'
 ```
 
 Note: If you are on a system with both Ruby 1.9 and Ruby 2.0 you may need to replace gem with gem2.0.

docs/building-spark.md

@@ -9,9 +9,9 @@ license: |
   The ASF licenses this file to You under the Apache License, Version 2.0
   (the "License"); you may not use this file except in compliance with
   the License.  You may obtain a copy of the License at
- 
+
      http://www.apache.org/licenses/LICENSE-2.0
- 
+
   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
@@ -70,9 +70,9 @@ This will build Spark distribution along with Python pip and R packages. For mor
 
 ## Specifying the Hadoop Version and Enabling YARN
 
-You can specify the exact version of Hadoop to compile against through the `hadoop.version` property. 
+You can specify the exact version of Hadoop to compile against through the `hadoop.version` property.
 
-You can enable the `yarn` profile and optionally set the `yarn.version` property if it is different 
+You can enable the `yarn` profile and optionally set the `yarn.version` property if it is different
 from `hadoop.version`.
 
 Example:
@@ -238,8 +238,7 @@ The run-tests script also can be limited to a specific Python version or a speci
 
 To run the SparkR tests you will need to install the [knitr](https://cran.r-project.org/package=knitr), [rmarkdown](https://cran.r-project.org/package=rmarkdown), [testthat](https://cran.r-project.org/package=testthat), [e1071](https://cran.r-project.org/package=e1071) and [survival](https://cran.r-project.org/package=survival) packages first:
 
-    Rscript -e "install.packages(c('knitr', 'rmarkdown', 'devtools', 'e1071', 'survival'), repos='https://cloud.r-project.org/')"
-    Rscript -e "devtools::install_version('testthat', version = '1.0.2', repos='https://cloud.r-project.org/')"
+    Rscript -e "install.packages(c('knitr', 'rmarkdown', 'devtools', 'testthat', 'e1071', 'survival'), repos='https://cloud.r-project.org/')"
 
 You can run just the SparkR tests using the command: