Silent Failure with Partial Rows
#### I was trying to read a file that looked like this (unbeknownst to me):

```text
1,
2, 1.23, 4.56
3, 1.24, 4.57
4, 1.25, 4.58
...
```
I wrote some code like this:
```python
import pandas as pd
pd.read_csv('file.txt').values

```
And the output I got looked liked this:
```python
[[nan]
 [nan]
 [nan]
 ...
 [nan]
 [nan]
 [nan]]
```
#### Problem description

When I try to parse a text file that has partial rows, pandas silently fails by importing an array of NaNs. It should instead throw an error.

#### Expected Output

'Error: partial rows'

#### Output of ``pd.show_versions()``

<details>
INSTALLED VERSIONS
------------------
commit: None
python: 3.6.5.final.0
python-bits: 64
OS: Linux
OS-release: 4.15.0-24-generic
machine: x86_64
processor: x86_64
byteorder: little
LC_ALL: None
LANG: en_US.UTF-8
LOCALE: en_US.UTF-8

pandas: 0.23.0
pytest: 3.5.1
pip: 18.0
setuptools: 39.1.0
Cython: 0.28.2
numpy: 1.14.3
scipy: 1.1.0
pyarrow: None
xarray: None
IPython: 6.4.0
sphinx: 1.7.4
patsy: 0.5.0
dateutil: 2.7.3
pytz: 2018.4
blosc: None
bottleneck: 1.2.1
tables: 3.4.3
numexpr: 2.6.5
feather: None
matplotlib: 2.2.2
openpyxl: 2.5.3
xlrd: 1.1.0
xlwt: 1.3.0
xlsxwriter: 1.0.4
lxml: 4.2.1
bs4: 4.6.0
html5lib: 1.0.1
sqlalchemy: 1.2.7
pymysql: None
psycopg2: None
jinja2: 2.10
s3fs: None
fastparquet: None
pandas_gbq: None
pandas_datareader: None

</details>
