From 3aa712c32b129af024c9d1107d0c83b8df58517b Mon Sep 17 00:00:00 2001
From: Dominik Stadler <centic@apache.org>
Date: Tue, 6 Apr 2021 06:11:01 +0000
Subject: [PATCH] XSLX2CSV: Do not double-encode if the value is already having
 quotes and escape double-quotes

Most CSV formats use "" (two quotes) to escape a "-character, we should do this in this
example as well to produce files that can be parsed by other CSV processors correctly.

Also cases where the value is already enclosed in quotes should not lead to additional quotes

Add a simple initial test to module "examples" verify basic functionality of XSLX2CSV
as I often rely on it for converting some very large xlsx-files to csv

git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@1888418 13f79535-47bb-0310-9956-ffa450edef68
---
 examples/build.gradle                          |  3 +++
 .../examples/xssf/eventusermodel/XLSX2CSV.java | 14 +++++++++++++-
 ooxml/build.gradle                             | 18 ++++++++++++++----
 3 files changed, 30 insertions(+), 5 deletions(-)

diff --git a/examples/build.gradle b/examples/build.gradle
index 559dd449cc..15ab280aa1 100644
--- a/examples/build.gradle
+++ b/examples/build.gradle
@@ -20,4 +20,7 @@ dependencies {
     implementation project(':scratchpad')
 
     implementation "org.apache.logging.log4j:log4j-core:${log4jVersion}"
+
+	testImplementation project(path: ':ooxml', configuration: 'tests')
+	testImplementation project(path: ':main', configuration: 'tests')
 }
diff --git a/examples/src/main/java/org/apache/poi/examples/xssf/eventusermodel/XLSX2CSV.java b/examples/src/main/java/org/apache/poi/examples/xssf/eventusermodel/XLSX2CSV.java
index 627e0f7fb5..81235f0ef5 100644
--- a/examples/src/main/java/org/apache/poi/examples/xssf/eventusermodel/XLSX2CSV.java
+++ b/examples/src/main/java/org/apache/poi/examples/xssf/eventusermodel/XLSX2CSV.java
@@ -128,6 +128,12 @@ public class XLSX2CSV {
             for (int i=0; i<missedCols; i++) {
                 output.append(',');
             }
+
+            // no need to append anything if we do not have a value
+            if (formattedValue == null) {
+                return;
+            }
+
             currentCol = thisCol;
 
             // Number or string?
@@ -136,8 +142,14 @@ public class XLSX2CSV {
                 Double.parseDouble(formattedValue);
                 output.append(formattedValue);
             } catch (Exception e) {
+                // let's remove quotes if they are already there
+                if (formattedValue.startsWith("\"") && formattedValue.endsWith("\"")) {
+                    formattedValue = formattedValue.substring(1, formattedValue.length()-1);
+                }
+
                 output.append('"');
-                output.append(formattedValue);
+                // encode double-quote with two double-quotes to produce a valid CSV format
+                output.append(formattedValue.replace("\"", "\"\""));
                 output.append('"');
             }
         }
diff --git a/ooxml/build.gradle b/ooxml/build.gradle
index 2937e482bf..3fac94efbe 100644
--- a/ooxml/build.gradle
+++ b/ooxml/build.gradle
@@ -50,7 +50,17 @@ jar {
     }
 }
 
-test {
-    // for some reason catching the OOM does not work when run from Gradle
-    exclude '**/MemoryUsage.class'
-}
\ No newline at end of file
+// Create a separate jar for test-code to depend on it in other projects
+// See http://stackoverflow.com/questions/5144325/gradle-test-dependency
+task testJar(type: Jar, dependsOn: testClasses) {
+	baseName = "test-${project.archivesBaseName}"
+	from sourceSets.test.output
+}
+
+configurations {
+	tests
+}
+
+artifacts {
+	tests testJar
+}