Examples of correct and incorrect pinyin Where to find an authoritative and/or verified list of examples for correct (and incorrect) Chinese to Pinyin conversions for words and sentences?
I am specifically looking for corner cases when automated Chinese (simplified/traditional) conversion to pinyin might fail so that I can build a test case to verify correctness.
For example, the character 呢 could be translated to pinyin as any of ne5,ni2,na4, or ne4 and it looks like some libraries are getting it wrong in certain contexts.
An idea coming from here suggests to take the HSK vocabulary list annotated with pinyin and put the words list to Google translate. The post's author found 11% of words incorrectly converted for HSK level 1-3 words.
The issue is that the official HSK website provides only a words-list without pinyin in an excel format. However, you can find respectively here and here words-lists annotated with pinyin in a pdf or on a website which you can later programmatically convert in a suitable format.
EDIT, in comments:

HSK wordlist with pinyin in tab-separated values